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-rw-r--r--drivers/i2c/busses/i2c-imx.c1848
1 files changed, 1592 insertions, 256 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index e24279725d36..dcce882f3eba 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -1,21 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2002 Motorola GSG-China
*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
- * USA.
- *
* Author:
* Darius Augulis, Teltonika Inc.
*
@@ -30,44 +16,76 @@
* Copyright (C) 2007 RightHand Technologies, Inc.
* Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
*
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ * Copyright 2020, 2024 NXP
+ *
*/
-/** Includes *******************************************************************
-*******************************************************************************/
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/interrupt.h>
+#include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/cleanup.h>
+#include <linux/completion.h>
#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/dmapool.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
-#include <linux/sched.h>
-#include <linux/platform_device.h>
-#include <linux/clk.h>
-#include <linux/slab.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/hrtimer.h>
+#include <linux/module.h>
#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/of_i2c.h>
+#include <linux/of_dma.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_data/i2c-imx.h>
-
-/** Defines ********************************************************************
-*******************************************************************************/
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
/* This will be the driver name the kernel reports */
#define DRIVER_NAME "imx-i2c"
-/* Default value */
-#define IMX_I2C_BIT_RATE 100000 /* 100kHz */
+#define I2C_IMX_CHECK_DELAY 30000 /* Time to check for bus idle, in NS */
-/* IMX I2C registers */
+/*
+ * Enable DMA if transfer byte size is bigger than this threshold.
+ * As the hardware request, it must bigger than 4 bytes.\
+ * I have set '16' here, maybe it's not the best but I think it's
+ * the appropriate.
+ */
+#define DMA_THRESHOLD 16
+#define DMA_TIMEOUT 1000
+
+/* IMX I2C registers:
+ * the I2C register offset is different between SoCs,
+ * to provide support for all these chips, split the
+ * register offset into a fixed base address and a
+ * variable shift value, then the full register offset
+ * will be calculated by
+ * reg_off = ( reg_base_addr << reg_shift)
+ */
#define IMX_I2C_IADR 0x00 /* i2c slave address */
-#define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
-#define IMX_I2C_I2CR 0x08 /* i2c control */
-#define IMX_I2C_I2SR 0x0C /* i2c status */
-#define IMX_I2C_I2DR 0x10 /* i2c transfer data */
+#define IMX_I2C_IFDR 0x01 /* i2c frequency divider */
+#define IMX_I2C_I2CR 0x02 /* i2c control */
+#define IMX_I2C_I2SR 0x03 /* i2c status */
+#define IMX_I2C_I2DR 0x04 /* i2c transfer data */
+
+/*
+ * All of the layerscape series SoCs support IBIC register.
+ */
+#define IMX_I2C_IBIC 0x05 /* i2c bus interrupt config */
+
+#define IMX_I2C_REGSHIFT 2
+#define VF610_I2C_REGSHIFT 0
+#define S32G_I2C_REGSHIFT 0
/* Bits of IMX I2C registers */
#define I2SR_RXAK 0x01
@@ -77,15 +95,29 @@
#define I2SR_IBB 0x20
#define I2SR_IAAS 0x40
#define I2SR_ICF 0x80
+#define I2CR_DMAEN 0x02
#define I2CR_RSTA 0x04
#define I2CR_TXAK 0x08
#define I2CR_MTX 0x10
#define I2CR_MSTA 0x20
#define I2CR_IIEN 0x40
#define I2CR_IEN 0x80
+#define IBIC_BIIE 0x80 /* Bus idle interrupt enable */
+
+/* register bits different operating codes definition:
+ * 1) I2SR: Interrupt flags clear operation differ between SoCs:
+ * - write zero to clear(w0c) INT flag on i.MX,
+ * - but write one to clear(w1c) INT flag on Vybrid.
+ * 2) I2CR: I2C module enable operation also differ between SoCs:
+ * - set I2CR_IEN bit enable the module on i.MX,
+ * - but clear I2CR_IEN bit enable the module on Vybrid.
+ */
+#define I2SR_CLR_OPCODE_W0C 0x0
+#define I2SR_CLR_OPCODE_W1C (I2SR_IAL | I2SR_IIF)
+#define I2CR_IEN_OPCODE_0 0x0
+#define I2CR_IEN_OPCODE_1 I2CR_IEN
-/** Variables ******************************************************************
-*******************************************************************************/
+#define I2C_PM_TIMEOUT 10 /* ms */
/*
* sorted list of clock divider, register value pairs
@@ -95,8 +127,12 @@
*
* Duplicated divider values removed from list
*/
+struct imx_i2c_clk_pair {
+ u16 div;
+ u16 val;
+};
-static u16 __initdata i2c_clk_div[50][2] = {
+static struct imx_i2c_clk_pair imx_i2c_clk_div[] = {
{ 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
{ 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
{ 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
@@ -112,30 +148,180 @@ static u16 __initdata i2c_clk_div[50][2] = {
{ 3072, 0x1E }, { 3840, 0x1F }
};
+/* Vybrid VF610 clock divider, register value pairs */
+static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = {
+ { 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 },
+ { 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 },
+ { 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D },
+ { 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 },
+ { 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 },
+ { 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 },
+ { 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 },
+ { 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 },
+ { 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 },
+ { 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B },
+ { 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 },
+ { 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
+ { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
+ { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
+ { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
+};
+
+/* S32G2/S32G3 clock divider, register value pairs */
+static struct imx_i2c_clk_pair s32g2_i2c_clk_div[] = {
+ { 34, 0x00 }, { 36, 0x01 }, { 38, 0x02 }, { 40, 0x03 },
+ { 42, 0x04 }, { 44, 0x05 }, { 46, 0x06 }, { 48, 0x09 },
+ { 52, 0x0A }, { 54, 0x07 }, { 56, 0x0B }, { 60, 0x0C },
+ { 64, 0x0D }, { 68, 0x40 }, { 72, 0x0E }, { 76, 0x42 },
+ { 80, 0x12 }, { 84, 0x0F }, { 88, 0x13 }, { 96, 0x14 },
+ { 104, 0x15 }, { 108, 0x47 }, { 112, 0x19 }, { 120, 0x16 },
+ { 128, 0x1A }, { 136, 0x80 }, { 144, 0x17 }, { 152, 0x82 },
+ { 160, 0x1C }, { 168, 0x84 }, { 176, 0x1D }, { 192, 0x21 },
+ { 208, 0x1E }, { 216, 0x87 }, { 224, 0x22 }, { 240, 0x56 },
+ { 256, 0x1F }, { 288, 0x24 }, { 320, 0x25 }, { 336, 0x8F },
+ { 352, 0x93 }, { 356, 0x5D }, { 358, 0x98 }, { 384, 0x26 },
+ { 416, 0x56 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B },
+ { 576, 0x2C }, { 640, 0x2D }, { 704, 0x9D }, { 768, 0x2E },
+ { 832, 0x9D }, { 896, 0x32 }, { 960, 0x2F }, { 1024, 0x33 },
+ { 1152, 0x34 }, { 1280, 0x35 }, { 1536, 0x36 }, { 1792, 0x3A },
+ { 1920, 0x37 }, { 2048, 0x3B }, { 2304, 0x74 }, { 2560, 0x3D },
+ { 3072, 0x3E }, { 3584, 0x7A }, { 3840, 0x3F }, { 4096, 0x7B },
+ { 4608, 0x7C }, { 5120, 0x7D }, { 6144, 0x7E }, { 7168, 0xBA },
+ { 7680, 0x7F }, { 8192, 0xBB }, { 9216, 0xBC }, { 10240, 0xBD },
+ { 12288, 0xBE }, { 15360, 0xBF },
+};
+
enum imx_i2c_type {
IMX1_I2C,
IMX21_I2C,
+ S32G_I2C,
+ VF610_I2C,
+};
+
+struct imx_i2c_hwdata {
+ enum imx_i2c_type devtype;
+ unsigned int regshift;
+ struct imx_i2c_clk_pair *clk_div;
+ unsigned int ndivs;
+ unsigned int i2sr_clr_opcode;
+ unsigned int i2cr_ien_opcode;
+ /*
+ * Errata ERR007805 or e7805:
+ * I2C: When the I2C clock speed is configured for 400 kHz,
+ * the SCL low period violates the I2C spec of 1.3 uS min.
+ */
+ bool has_err007805;
+};
+
+struct imx_i2c_dma {
+ struct dma_chan *chan_tx;
+ struct dma_chan *chan_rx;
+ struct dma_chan *chan_using;
+ struct completion cmd_complete;
+ dma_addr_t dma_buf;
+ unsigned int dma_len;
+ enum dma_transfer_direction dma_transfer_dir;
+ enum dma_data_direction dma_data_dir;
+};
+
+enum imx_i2c_state {
+ IMX_I2C_STATE_DONE,
+ IMX_I2C_STATE_FAILED,
+ IMX_I2C_STATE_WRITE,
+ IMX_I2C_STATE_DMA,
+ IMX_I2C_STATE_READ,
+ IMX_I2C_STATE_READ_CONTINUE,
+ IMX_I2C_STATE_READ_BLOCK_DATA,
+ IMX_I2C_STATE_READ_BLOCK_DATA_LEN,
};
struct imx_i2c_struct {
struct i2c_adapter adapter;
struct clk *clk;
+ struct notifier_block clk_change_nb;
void __iomem *base;
wait_queue_head_t queue;
unsigned long i2csr;
- unsigned int disable_delay;
+ unsigned int disable_delay;
int stopped;
unsigned int ifdr; /* IMX_I2C_IFDR */
- enum imx_i2c_type devtype;
+ unsigned int cur_clk;
+ unsigned int bitrate;
+ const struct imx_i2c_hwdata *hwdata;
+ struct i2c_bus_recovery_info rinfo;
+
+ struct imx_i2c_dma *dma;
+ struct i2c_client *slave;
+ enum i2c_slave_event last_slave_event;
+
+ struct i2c_msg *msg;
+ unsigned int msg_buf_idx;
+ int isr_result;
+ bool is_lastmsg;
+ enum imx_i2c_state state;
+
+ bool multi_master;
+
+ /* For checking slave events. */
+ spinlock_t slave_lock;
+ struct hrtimer slave_timer;
+};
+
+static const struct imx_i2c_hwdata imx1_i2c_hwdata = {
+ .devtype = IMX1_I2C,
+ .regshift = IMX_I2C_REGSHIFT,
+ .clk_div = imx_i2c_clk_div,
+ .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
+ .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
+ .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
+
};
-static struct platform_device_id imx_i2c_devtype[] = {
+static const struct imx_i2c_hwdata imx21_i2c_hwdata = {
+ .devtype = IMX21_I2C,
+ .regshift = IMX_I2C_REGSHIFT,
+ .clk_div = imx_i2c_clk_div,
+ .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
+ .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
+ .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
+
+};
+
+static const struct imx_i2c_hwdata imx6_i2c_hwdata = {
+ .devtype = IMX21_I2C,
+ .regshift = IMX_I2C_REGSHIFT,
+ .clk_div = imx_i2c_clk_div,
+ .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
+ .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
+ .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
+ .has_err007805 = true,
+};
+
+static struct imx_i2c_hwdata vf610_i2c_hwdata = {
+ .devtype = VF610_I2C,
+ .regshift = VF610_I2C_REGSHIFT,
+ .clk_div = vf610_i2c_clk_div,
+ .ndivs = ARRAY_SIZE(vf610_i2c_clk_div),
+ .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C,
+ .i2cr_ien_opcode = I2CR_IEN_OPCODE_0,
+};
+
+static const struct imx_i2c_hwdata s32g2_i2c_hwdata = {
+ .devtype = S32G_I2C,
+ .regshift = S32G_I2C_REGSHIFT,
+ .clk_div = s32g2_i2c_clk_div,
+ .ndivs = ARRAY_SIZE(s32g2_i2c_clk_div),
+ .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C,
+ .i2cr_ien_opcode = I2CR_IEN_OPCODE_0,
+};
+
+static const struct platform_device_id imx_i2c_devtype[] = {
{
.name = "imx1-i2c",
- .driver_data = IMX1_I2C,
+ .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata,
}, {
.name = "imx21-i2c",
- .driver_data = IMX21_I2C,
+ .driver_data = (kernel_ulong_t)&imx21_i2c_hwdata,
}, {
/* sentinel */
}
@@ -143,52 +329,284 @@ static struct platform_device_id imx_i2c_devtype[] = {
MODULE_DEVICE_TABLE(platform, imx_i2c_devtype);
static const struct of_device_id i2c_imx_dt_ids[] = {
- { .compatible = "fsl,imx1-i2c", .data = &imx_i2c_devtype[IMX1_I2C], },
- { .compatible = "fsl,imx21-i2c", .data = &imx_i2c_devtype[IMX21_I2C], },
+ { .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, },
+ { .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, },
+ { .compatible = "fsl,imx6q-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx6sl-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx6sll-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx6sx-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx6ul-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx7d-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx7s-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx8mm-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx8mn-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx8mp-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx8mq-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, },
+ { .compatible = "nxp,s32g2-i2c", .data = &s32g2_i2c_hwdata, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids);
+static const struct acpi_device_id i2c_imx_acpi_ids[] = {
+ {"NXP0001", .driver_data = (kernel_ulong_t)&vf610_i2c_hwdata},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, i2c_imx_acpi_ids);
+
static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
{
- return i2c_imx->devtype == IMX1_I2C;
+ return i2c_imx->hwdata->devtype == IMX1_I2C;
+}
+
+static inline int is_vf610_i2c(struct imx_i2c_struct *i2c_imx)
+{
+ return i2c_imx->hwdata->devtype == VF610_I2C;
}
-/** Functions for IMX I2C adapter driver ***************************************
-*******************************************************************************/
+static inline void imx_i2c_write_reg(unsigned int val,
+ struct imx_i2c_struct *i2c_imx, unsigned int reg)
+{
+ writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
+}
-static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
+static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
+ unsigned int reg)
+{
+ return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
+}
+
+static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits)
{
- unsigned long orig_jiffies = jiffies;
unsigned int temp;
- dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
+ /*
+ * i2sr_clr_opcode is the value to clear all interrupts. Here we want to
+ * clear only <bits>, so we write ~i2sr_clr_opcode with just <bits>
+ * toggled. This is required because i.MX needs W0C and Vybrid uses W1C.
+ */
+ temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
+}
+
+/* Set up i2c controller register and i2c status register to default value. */
+static void i2c_imx_reset_regs(struct imx_i2c_struct *i2c_imx)
+{
+ imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
+ i2c_imx, IMX_I2C_I2CR);
+ i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
+}
+
+/* Functions for DMA support */
+static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, dma_addr_t phy_addr)
+{
+ struct imx_i2c_dma *dma;
+ struct dma_slave_config dma_sconfig;
+ struct device *dev = i2c_imx->adapter.dev.parent;
+ int ret;
+
+ dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
+ if (!dma)
+ return -ENOMEM;
+
+ dma->chan_tx = dma_request_chan(dev, "tx");
+ if (IS_ERR(dma->chan_tx)) {
+ ret = PTR_ERR(dma->chan_tx);
+ if (ret != -ENODEV && ret != -EPROBE_DEFER)
+ dev_err(dev, "can't request DMA tx channel (%d)\n", ret);
+ goto fail_al;
+ }
+
+ dma_sconfig.dst_addr = phy_addr +
+ (IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
+ dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ dma_sconfig.dst_maxburst = 1;
+ dma_sconfig.direction = DMA_MEM_TO_DEV;
+ ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig);
+ if (ret < 0) {
+ dev_err(dev, "can't configure tx channel (%d)\n", ret);
+ goto fail_tx;
+ }
+
+ dma->chan_rx = dma_request_chan(dev, "rx");
+ if (IS_ERR(dma->chan_rx)) {
+ ret = PTR_ERR(dma->chan_rx);
+ if (ret != -ENODEV && ret != -EPROBE_DEFER)
+ dev_err(dev, "can't request DMA rx channel (%d)\n", ret);
+ goto fail_tx;
+ }
+
+ dma_sconfig.src_addr = phy_addr +
+ (IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
+ dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ dma_sconfig.src_maxburst = 1;
+ dma_sconfig.direction = DMA_DEV_TO_MEM;
+ ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig);
+ if (ret < 0) {
+ dev_err(dev, "can't configure rx channel (%d)\n", ret);
+ goto fail_rx;
+ }
+
+ i2c_imx->dma = dma;
+ init_completion(&dma->cmd_complete);
+ dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
+ dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
+
+ return 0;
+
+fail_rx:
+ dma_release_channel(dma->chan_rx);
+fail_tx:
+ dma_release_channel(dma->chan_tx);
+fail_al:
+ devm_kfree(dev, dma);
+
+ return ret;
+}
+
+static void i2c_imx_dma_callback(void *arg)
+{
+ struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg;
+ struct imx_i2c_dma *dma = i2c_imx->dma;
+
+ dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf,
+ dma->dma_len, dma->dma_data_dir);
+ complete(&dma->cmd_complete);
+}
+
+static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx,
+ struct i2c_msg *msgs)
+{
+ struct imx_i2c_dma *dma = i2c_imx->dma;
+ struct dma_async_tx_descriptor *txdesc;
+ struct device *dev = &i2c_imx->adapter.dev;
+ struct device *chan_dev = dma->chan_using->device->dev;
+
+ dma->dma_buf = dma_map_single(chan_dev, msgs->buf,
+ dma->dma_len, dma->dma_data_dir);
+ if (dma_mapping_error(chan_dev, dma->dma_buf)) {
+ dev_err(dev, "DMA mapping failed\n");
+ goto err_map;
+ }
+
+ txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf,
+ dma->dma_len, dma->dma_transfer_dir,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!txdesc) {
+ dev_err(dev, "Not able to get desc for DMA xfer\n");
+ goto err_desc;
+ }
+
+ reinit_completion(&dma->cmd_complete);
+ txdesc->callback = i2c_imx_dma_callback;
+ txdesc->callback_param = i2c_imx;
+ if (dma_submit_error(dmaengine_submit(txdesc))) {
+ dev_err(dev, "DMA submit failed\n");
+ goto err_submit;
+ }
+
+ dma_async_issue_pending(dma->chan_using);
+ return 0;
+
+err_submit:
+ dmaengine_terminate_sync(dma->chan_using);
+err_desc:
+ dma_unmap_single(chan_dev, dma->dma_buf,
+ dma->dma_len, dma->dma_data_dir);
+err_map:
+ return -EINVAL;
+}
+
+static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
+{
+ struct imx_i2c_dma *dma = i2c_imx->dma;
+
+ dma->dma_buf = 0;
+ dma->dma_len = 0;
+
+ dma_release_channel(dma->chan_tx);
+ dma->chan_tx = NULL;
+
+ dma_release_channel(dma->chan_rx);
+ dma->chan_rx = NULL;
+
+ dma->chan_using = NULL;
+}
+
+static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic)
+{
+ bool multi_master = i2c_imx->multi_master;
+ unsigned long orig_jiffies = jiffies;
+ unsigned int temp;
while (1) {
- temp = readb(i2c_imx->base + IMX_I2C_I2SR);
- if (for_busy && (temp & I2SR_IBB))
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
+
+ /* check for arbitration lost */
+ if (multi_master && (temp & I2SR_IAL)) {
+ i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
+ return -EAGAIN;
+ }
+
+ if (for_busy && (!multi_master || (temp & I2SR_IBB))) {
+ i2c_imx->stopped = 0;
break;
- if (!for_busy && !(temp & I2SR_IBB))
+ }
+ if (!for_busy && !(temp & I2SR_IBB)) {
+ i2c_imx->stopped = 1;
break;
+ }
if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
dev_dbg(&i2c_imx->adapter.dev,
"<%s> I2C bus is busy\n", __func__);
return -ETIMEDOUT;
}
- schedule();
+ if (atomic)
+ udelay(100);
+ else
+ schedule();
}
return 0;
}
-static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
+static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic)
{
- wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
+ if (atomic) {
+ void __iomem *addr = i2c_imx->base + (IMX_I2C_I2SR << i2c_imx->hwdata->regshift);
+ unsigned int regval;
+
+ /*
+ * The formula for the poll timeout is documented in the RM
+ * Rev.5 on page 1878:
+ * T_min = 10/F_scl
+ * Set the value hard as it is done for the non-atomic use-case.
+ * Use 10 kHz for the calculation since this is the minimum
+ * allowed SMBus frequency. Also add an offset of 100us since it
+ * turned out that the I2SR_IIF bit isn't set correctly within
+ * the minimum timeout in polling mode.
+ */
+ readb_poll_timeout_atomic(addr, regval, regval & I2SR_IIF, 5, 1000 + 100);
+ i2c_imx->i2csr = regval;
+ i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
+ } else {
+ wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
+ }
if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
return -ETIMEDOUT;
}
+
+ /* In multi-master mode check for arbitration lost */
+ if (i2c_imx->multi_master && (i2c_imx->i2csr & I2SR_IAL)) {
+ dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__);
+ i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
+
+ i2c_imx->i2csr = 0;
+ return -EAGAIN;
+ }
+
dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
i2c_imx->i2csr = 0;
return 0;
@@ -196,55 +614,131 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
{
- if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
+ if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
- return -EIO; /* No ACK */
+ return -ENXIO; /* No ACK */
}
dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
return 0;
}
-static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
+static int i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
+ unsigned int i2c_clk_rate)
+{
+ struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div;
+ unsigned int div;
+ int i;
+
+ if (i2c_imx->hwdata->has_err007805 && i2c_imx->bitrate > 384000) {
+ dev_dbg(&i2c_imx->adapter.dev,
+ "SoC errata ERR007805 or e7805 applies, bus frequency limited from %d Hz to 384000 Hz.\n",
+ i2c_imx->bitrate);
+ i2c_imx->bitrate = 384000;
+ }
+
+ /* Divider value calculation */
+ if (i2c_imx->cur_clk == i2c_clk_rate)
+ return 0;
+
+ /* Keep the denominator of the following program always NOT equal to 0. */
+ if (!(i2c_clk_rate / 2))
+ return -EINVAL;
+
+ i2c_imx->cur_clk = i2c_clk_rate;
+
+ div = DIV_ROUND_UP(i2c_clk_rate, i2c_imx->bitrate);
+ if (div < i2c_clk_div[0].div)
+ i = 0;
+ else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div)
+ i = i2c_imx->hwdata->ndivs - 1;
+ else
+ for (i = 0; i2c_clk_div[i].div < div; i++)
+ ;
+
+ /* Store divider value */
+ i2c_imx->ifdr = i2c_clk_div[i].val;
+
+ /*
+ * There dummy delay is calculated.
+ * It should be about one I2C clock period long.
+ * This delay is used in I2C bus disable function
+ * to fix chip hardware bug.
+ */
+ i2c_imx->disable_delay = DIV_ROUND_UP(500000U * i2c_clk_div[i].div,
+ i2c_clk_rate / 2);
+
+#ifdef CONFIG_I2C_DEBUG_BUS
+ dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n",
+ i2c_clk_rate, div);
+ dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n",
+ i2c_clk_div[i].val, i2c_clk_div[i].div);
+#endif
+
+ return 0;
+}
+
+static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct clk_notifier_data *ndata = data;
+ struct imx_i2c_struct *i2c_imx = container_of(nb,
+ struct imx_i2c_struct,
+ clk_change_nb);
+ int ret = 0;
+
+ if (action & POST_RATE_CHANGE)
+ ret = i2c_imx_set_clk(i2c_imx, ndata->new_rate);
+
+ return notifier_from_errno(ret);
+}
+
+static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic)
{
unsigned int temp = 0;
int result;
- dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
-
- clk_prepare_enable(i2c_imx->clk);
- writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
+ imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR);
/* Enable I2C controller */
- writeb(0, i2c_imx->base + IMX_I2C_I2SR);
- writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
+ imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
+ imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR);
/* Wait controller to be stable */
- udelay(50);
+ if (atomic)
+ udelay(50);
+ else
+ usleep_range(50, 150);
/* Start I2C transaction */
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
temp |= I2CR_MSTA;
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
- result = i2c_imx_bus_busy(i2c_imx, 1);
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ result = i2c_imx_bus_busy(i2c_imx, 1, atomic);
if (result)
return result;
- i2c_imx->stopped = 0;
temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+ if (atomic)
+ temp &= ~I2CR_IIEN; /* Disable interrupt */
+
+ temp &= ~I2CR_DMAEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
return result;
}
-static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
+static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic)
{
unsigned int temp = 0;
if (!i2c_imx->stopped) {
/* Stop I2C transaction */
- dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
temp &= ~(I2CR_MSTA | I2CR_MTX);
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+ if (i2c_imx->dma)
+ temp &= ~I2CR_DMAEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
}
if (is_imx1_i2c(i2c_imx)) {
/*
@@ -254,82 +748,611 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
udelay(i2c_imx->disable_delay);
}
- if (!i2c_imx->stopped) {
- i2c_imx_bus_busy(i2c_imx, 0);
- i2c_imx->stopped = 1;
- }
+ if (!i2c_imx->stopped)
+ i2c_imx_bus_busy(i2c_imx, 0, atomic);
/* Disable I2C controller */
- writeb(0, i2c_imx->base + IMX_I2C_I2CR);
- clk_disable_unprepare(i2c_imx->clk);
+ temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
}
-static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
- unsigned int rate)
+/*
+ * Enable bus idle interrupts
+ * Note: IBIC register will be cleared after disabled i2c module.
+ * All of layerscape series SoCs support IBIC register.
+ */
+static void i2c_imx_enable_bus_idle(struct imx_i2c_struct *i2c_imx)
{
- unsigned int i2c_clk_rate;
- unsigned int div;
- int i;
+ if (is_vf610_i2c(i2c_imx)) {
+ unsigned int temp;
- /* Divider value calculation */
- i2c_clk_rate = clk_get_rate(i2c_imx->clk);
- div = (i2c_clk_rate + rate - 1) / rate;
- if (div < i2c_clk_div[0][0])
- i = 0;
- else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
- i = ARRAY_SIZE(i2c_clk_div) - 1;
- else
- for (i = 0; i2c_clk_div[i][0] < div; i++);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_IBIC);
+ temp |= IBIC_BIIE;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_IBIC);
+ }
+}
- /* Store divider value */
- i2c_imx->ifdr = i2c_clk_div[i][1];
+static void i2c_imx_slave_event(struct imx_i2c_struct *i2c_imx,
+ enum i2c_slave_event event, u8 *val)
+{
+ i2c_slave_event(i2c_imx->slave, event, val);
+ i2c_imx->last_slave_event = event;
+}
+static void i2c_imx_slave_finish_op(struct imx_i2c_struct *i2c_imx)
+{
+ u8 val = 0;
+
+ while (i2c_imx->last_slave_event != I2C_SLAVE_STOP) {
+ switch (i2c_imx->last_slave_event) {
+ case I2C_SLAVE_READ_REQUESTED:
+ i2c_imx_slave_event(i2c_imx, I2C_SLAVE_READ_PROCESSED,
+ &val);
+ break;
+
+ case I2C_SLAVE_WRITE_REQUESTED:
+ case I2C_SLAVE_READ_PROCESSED:
+ case I2C_SLAVE_WRITE_RECEIVED:
+ i2c_imx_slave_event(i2c_imx, I2C_SLAVE_STOP, &val);
+ break;
+
+ case I2C_SLAVE_STOP:
+ break;
+ }
+ }
+}
+
+/* Returns true if the timer should be restarted, false if not. */
+static irqreturn_t i2c_imx_slave_handle(struct imx_i2c_struct *i2c_imx,
+ unsigned int status, unsigned int ctl)
+{
+ u8 value = 0;
+
+ if (status & I2SR_IAL) { /* Arbitration lost */
+ i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
+ if (!(status & I2SR_IAAS))
+ return IRQ_HANDLED;
+ }
+
+ if (!(status & I2SR_IBB)) {
+ /* No master on the bus, that could mean a stop condition. */
+ i2c_imx_slave_finish_op(i2c_imx);
+ return IRQ_HANDLED;
+ }
+
+ if (!(status & I2SR_ICF))
+ /* Data transfer still in progress, ignore this. */
+ goto out;
+
+ if (status & I2SR_IAAS) { /* Addressed as a slave */
+ i2c_imx_slave_finish_op(i2c_imx);
+ if (status & I2SR_SRW) { /* Master wants to read from us*/
+ dev_dbg(&i2c_imx->adapter.dev, "read requested");
+ i2c_imx_slave_event(i2c_imx,
+ I2C_SLAVE_READ_REQUESTED, &value);
+
+ /* Slave transmit */
+ ctl |= I2CR_MTX;
+ imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
+
+ /* Send data */
+ imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR);
+ } else { /* Master wants to write to us */
+ dev_dbg(&i2c_imx->adapter.dev, "write requested");
+ i2c_imx_slave_event(i2c_imx,
+ I2C_SLAVE_WRITE_REQUESTED, &value);
+
+ /* Slave receive */
+ ctl &= ~I2CR_MTX;
+ imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
+ /* Dummy read */
+ imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+ }
+ } else if (!(ctl & I2CR_MTX)) { /* Receive mode */
+ value = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+ i2c_imx_slave_event(i2c_imx,
+ I2C_SLAVE_WRITE_RECEIVED, &value);
+ } else if (!(status & I2SR_RXAK)) { /* Transmit mode received ACK */
+ ctl |= I2CR_MTX;
+ imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
+
+ i2c_imx_slave_event(i2c_imx,
+ I2C_SLAVE_READ_PROCESSED, &value);
+
+ imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR);
+ } else { /* Transmit mode received NAK, operation is done */
+ ctl &= ~I2CR_MTX;
+ imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
+ imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+
+ /* flag the last byte as processed */
+ i2c_imx_slave_event(i2c_imx,
+ I2C_SLAVE_READ_PROCESSED, &value);
+
+ i2c_imx_slave_finish_op(i2c_imx);
+ return IRQ_HANDLED;
+ }
+
+out:
/*
- * There dummy delay is calculated.
- * It should be about one I2C clock period long.
- * This delay is used in I2C bus disable function
- * to fix chip hardware bug.
+ * No need to check the return value here. If it returns 0 or
+ * 1, then everything is fine. If it returns -1, then the
+ * timer is running in the handler. This will still work,
+ * though it may be redone (or already have been done) by the
+ * timer function.
*/
- i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
- + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
+ hrtimer_try_to_cancel(&i2c_imx->slave_timer);
+ hrtimer_forward_now(&i2c_imx->slave_timer, I2C_IMX_CHECK_DELAY);
+ hrtimer_restart(&i2c_imx->slave_timer);
+ return IRQ_HANDLED;
+}
- /* dev_dbg() can't be used, because adapter is not yet registered */
-#ifdef CONFIG_I2C_DEBUG_BUS
- dev_dbg(&i2c_imx->adapter.dev, "<%s> I2C_CLK=%d, REQ DIV=%d\n",
- __func__, i2c_clk_rate, div);
- dev_dbg(&i2c_imx->adapter.dev, "<%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
- __func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
-#endif
+static enum hrtimer_restart i2c_imx_slave_timeout(struct hrtimer *t)
+{
+ struct imx_i2c_struct *i2c_imx = container_of(t, struct imx_i2c_struct,
+ slave_timer);
+ unsigned int ctl, status;
+
+ guard(spinlock_irqsave)(&i2c_imx->slave_lock);
+
+ status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
+ ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ i2c_imx_slave_handle(i2c_imx, status, ctl);
+
+ return HRTIMER_NORESTART;
+}
+
+static void i2c_imx_slave_init(struct imx_i2c_struct *i2c_imx)
+{
+ int temp;
+
+ /* Set slave addr. */
+ imx_i2c_write_reg((i2c_imx->slave->addr << 1), i2c_imx, IMX_I2C_IADR);
+
+ i2c_imx_reset_regs(i2c_imx);
+
+ /* Enable module */
+ temp = i2c_imx->hwdata->i2cr_ien_opcode;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+
+ /* Enable interrupt from i2c module */
+ temp |= I2CR_IIEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+
+ i2c_imx_enable_bus_idle(i2c_imx);
+}
+
+static int i2c_imx_reg_slave(struct i2c_client *client)
+{
+ struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter);
+ int ret;
+
+ if (i2c_imx->slave)
+ return -EBUSY;
+
+ i2c_imx->slave = client;
+ i2c_imx->last_slave_event = I2C_SLAVE_STOP;
+
+ /* Resume */
+ ret = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent);
+ if (ret < 0) {
+ dev_err(&i2c_imx->adapter.dev, "failed to resume i2c controller");
+ return ret;
+ }
+
+ i2c_imx_slave_init(i2c_imx);
+
+ return 0;
+}
+
+static int i2c_imx_unreg_slave(struct i2c_client *client)
+{
+ struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter);
+ int ret;
+
+ if (!i2c_imx->slave)
+ return -EINVAL;
+
+ /* Reset slave address. */
+ imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
+
+ i2c_imx_reset_regs(i2c_imx);
+
+ i2c_imx->slave = NULL;
+
+ /* Suspend */
+ ret = pm_runtime_put_sync(i2c_imx->adapter.dev.parent);
+ if (ret < 0)
+ dev_err(&i2c_imx->adapter.dev, "failed to suspend i2c controller");
+
+ return ret;
+}
+
+static inline int i2c_imx_isr_acked(struct imx_i2c_struct *i2c_imx)
+{
+ i2c_imx->isr_result = 0;
+
+ if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
+ i2c_imx->state = IMX_I2C_STATE_FAILED;
+ i2c_imx->isr_result = -ENXIO;
+ wake_up(&i2c_imx->queue);
+ }
+
+ return i2c_imx->isr_result;
+}
+
+static inline int i2c_imx_isr_write(struct imx_i2c_struct *i2c_imx)
+{
+ int result;
+
+ result = i2c_imx_isr_acked(i2c_imx);
+ if (result)
+ return result;
+
+ if (i2c_imx->msg->len == i2c_imx->msg_buf_idx)
+ return 0;
+
+ imx_i2c_write_reg(i2c_imx->msg->buf[i2c_imx->msg_buf_idx++], i2c_imx, IMX_I2C_I2DR);
+
+ return 1;
+}
+
+static inline int i2c_imx_isr_read(struct imx_i2c_struct *i2c_imx)
+{
+ int result;
+ unsigned int temp;
+
+ result = i2c_imx_isr_acked(i2c_imx);
+ if (result)
+ return result;
+
+ /* setup bus to read data */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp &= ~I2CR_MTX;
+ if ((i2c_imx->msg->len - 1) || (i2c_imx->msg->flags & I2C_M_RECV_LEN))
+ temp &= ~I2CR_TXAK;
+
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
+
+ return 0;
+}
+
+static inline void i2c_imx_isr_read_continue(struct imx_i2c_struct *i2c_imx)
+{
+ unsigned int temp;
+
+ if ((i2c_imx->msg->len - 1) == i2c_imx->msg_buf_idx) {
+ if (i2c_imx->is_lastmsg) {
+ /*
+ * It must generate STOP before read I2DR to prevent
+ * controller from generating another clock cycle
+ */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
+ temp &= ~(I2CR_MSTA | I2CR_MTX);
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ } else {
+ /*
+ * For i2c master receiver repeat restart operation like:
+ * read -> repeat MSTA -> read/write
+ * The controller must set MTX before read the last byte in
+ * the first read operation, otherwise the first read cost
+ * one extra clock cycle.
+ */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp |= I2CR_MTX;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ }
+ } else if (i2c_imx->msg_buf_idx == (i2c_imx->msg->len - 2)) {
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp |= I2CR_TXAK;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ }
+
+ i2c_imx->msg->buf[i2c_imx->msg_buf_idx++] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+}
+
+static inline void i2c_imx_isr_read_block_data_len(struct imx_i2c_struct *i2c_imx)
+{
+ u8 len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+
+ if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) {
+ i2c_imx->isr_result = -EPROTO;
+ i2c_imx->state = IMX_I2C_STATE_FAILED;
+ wake_up(&i2c_imx->queue);
+ }
+ i2c_imx->msg->len += len;
+ i2c_imx->msg->buf[i2c_imx->msg_buf_idx++] = len;
+}
+
+static irqreturn_t i2c_imx_master_isr(struct imx_i2c_struct *i2c_imx, unsigned int status)
+{
+ /*
+ * This state machine handles I2C reception and transmission in non-DMA
+ * mode. We must process all the data in the ISR to reduce the delay
+ * between two consecutive messages. If the data is not processed in
+ * the ISR, SMBus devices may timeout, leading to a bus error.
+ */
+ switch (i2c_imx->state) {
+ case IMX_I2C_STATE_DMA:
+ i2c_imx->i2csr = status;
+ wake_up(&i2c_imx->queue);
+ break;
+
+ case IMX_I2C_STATE_READ:
+ if (i2c_imx_isr_read(i2c_imx))
+ break;
+ i2c_imx->state = IMX_I2C_STATE_READ_CONTINUE;
+ break;
+
+ case IMX_I2C_STATE_READ_CONTINUE:
+ i2c_imx_isr_read_continue(i2c_imx);
+ if (i2c_imx->msg_buf_idx == i2c_imx->msg->len) {
+ i2c_imx->state = IMX_I2C_STATE_DONE;
+ wake_up(&i2c_imx->queue);
+ }
+ break;
+
+ case IMX_I2C_STATE_READ_BLOCK_DATA:
+ if (i2c_imx_isr_read(i2c_imx))
+ break;
+ i2c_imx->state = IMX_I2C_STATE_READ_BLOCK_DATA_LEN;
+ break;
+
+ case IMX_I2C_STATE_READ_BLOCK_DATA_LEN:
+ i2c_imx_isr_read_block_data_len(i2c_imx);
+ i2c_imx->state = IMX_I2C_STATE_READ_CONTINUE;
+ break;
+
+ case IMX_I2C_STATE_WRITE:
+ if (i2c_imx_isr_write(i2c_imx))
+ break;
+ i2c_imx->state = IMX_I2C_STATE_DONE;
+ wake_up(&i2c_imx->queue);
+ break;
+
+ default:
+ i2c_imx->i2csr = status;
+ i2c_imx->state = IMX_I2C_STATE_FAILED;
+ i2c_imx->isr_result = -EINVAL;
+ wake_up(&i2c_imx->queue);
+ }
+
+ return IRQ_HANDLED;
}
static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
{
struct imx_i2c_struct *i2c_imx = dev_id;
+ unsigned int ctl, status;
+
+ scoped_guard(spinlock_irqsave, &i2c_imx->slave_lock) {
+ status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
+ ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+
+ if (!(status & I2SR_IIF))
+ return IRQ_NONE;
+
+ i2c_imx_clear_irq(i2c_imx, I2SR_IIF);
+
+ if (i2c_imx->slave) {
+ if (!(ctl & I2CR_MSTA))
+ return i2c_imx_slave_handle(i2c_imx,
+ status, ctl);
+
+ i2c_imx_slave_finish_op(i2c_imx);
+ }
+ }
+
+ return i2c_imx_master_isr(i2c_imx, status);
+}
+
+static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx,
+ struct i2c_msg *msgs)
+{
+ int result;
+ unsigned long time_left;
+ unsigned int temp = 0;
+ unsigned long orig_jiffies = jiffies;
+ struct imx_i2c_dma *dma = i2c_imx->dma;
+ struct device *dev = &i2c_imx->adapter.dev;
+
+ i2c_imx->state = IMX_I2C_STATE_DMA;
+
+ dma->chan_using = dma->chan_tx;
+ dma->dma_transfer_dir = DMA_MEM_TO_DEV;
+ dma->dma_data_dir = DMA_TO_DEVICE;
+ dma->dma_len = msgs->len - 1;
+ result = i2c_imx_dma_xfer(i2c_imx, msgs);
+ if (result)
+ return result;
+
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp |= I2CR_DMAEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+
+ /*
+ * Write slave address.
+ * The first byte must be transmitted by the CPU.
+ */
+ imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
+ time_left = wait_for_completion_timeout(
+ &i2c_imx->dma->cmd_complete,
+ msecs_to_jiffies(DMA_TIMEOUT));
+ if (time_left == 0) {
+ dmaengine_terminate_sync(dma->chan_using);
+ return -ETIMEDOUT;
+ }
+
+ /* Waiting for transfer complete. */
+ while (1) {
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
+ if (temp & I2SR_ICF)
+ break;
+ if (time_after(jiffies, orig_jiffies +
+ msecs_to_jiffies(DMA_TIMEOUT))) {
+ dev_dbg(dev, "<%s> Timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ schedule();
+ }
+
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp &= ~I2CR_DMAEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+
+ /* The last data byte must be transferred by the CPU. */
+ imx_i2c_write_reg(msgs->buf[msgs->len-1],
+ i2c_imx, IMX_I2C_I2DR);
+ result = i2c_imx_trx_complete(i2c_imx, false);
+ if (result)
+ return result;
+
+ return i2c_imx_acked(i2c_imx);
+}
+
+static int i2c_imx_prepare_read(struct imx_i2c_struct *i2c_imx,
+ struct i2c_msg *msgs, bool use_dma)
+{
+ int result;
+ unsigned int temp = 0;
+
+ /* write slave address */
+ imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
+ result = i2c_imx_trx_complete(i2c_imx, !use_dma);
+ if (result)
+ return result;
+ result = i2c_imx_acked(i2c_imx);
+ if (result)
+ return result;
+
+ dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
+
+ /* setup bus to read data */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp &= ~I2CR_MTX;
+
+ /*
+ * Reset the I2CR_TXAK flag initially for SMBus block read since the
+ * length is unknown
+ */
+ if (msgs->len - 1)
+ temp &= ~I2CR_TXAK;
+ if (use_dma)
+ temp |= I2CR_DMAEN;
+
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
+
+ return 0;
+}
+
+static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
+ struct i2c_msg *msgs, bool is_lastmsg)
+{
+ int result;
+ unsigned long time_left;
unsigned int temp;
+ unsigned long orig_jiffies = jiffies;
+ struct imx_i2c_dma *dma = i2c_imx->dma;
+ struct device *dev = &i2c_imx->adapter.dev;
- temp = readb(i2c_imx->base + IMX_I2C_I2SR);
- if (temp & I2SR_IIF) {
- /* save status register */
- i2c_imx->i2csr = temp;
- temp &= ~I2SR_IIF;
- writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
- wake_up(&i2c_imx->queue);
- return IRQ_HANDLED;
+ i2c_imx->state = IMX_I2C_STATE_DMA;
+
+ result = i2c_imx_prepare_read(i2c_imx, msgs, true);
+ if (result)
+ return result;
+
+ dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
+
+ dma->chan_using = dma->chan_rx;
+ dma->dma_transfer_dir = DMA_DEV_TO_MEM;
+ dma->dma_data_dir = DMA_FROM_DEVICE;
+ /* The last two data bytes must be transferred by the CPU. */
+ dma->dma_len = msgs->len - 2;
+ result = i2c_imx_dma_xfer(i2c_imx, msgs);
+ if (result)
+ return result;
+
+ time_left = wait_for_completion_timeout(
+ &i2c_imx->dma->cmd_complete,
+ msecs_to_jiffies(DMA_TIMEOUT));
+ if (time_left == 0) {
+ dmaengine_terminate_sync(dma->chan_using);
+ return -ETIMEDOUT;
+ }
+
+ /* waiting for transfer complete. */
+ while (1) {
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
+ if (temp & I2SR_ICF)
+ break;
+ if (time_after(jiffies, orig_jiffies +
+ msecs_to_jiffies(DMA_TIMEOUT))) {
+ dev_dbg(dev, "<%s> Timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ schedule();
+ }
+
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp &= ~I2CR_DMAEN;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+
+ /* read n-1 byte data */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp |= I2CR_TXAK;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+
+ msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+ /* read n byte data */
+ result = i2c_imx_trx_complete(i2c_imx, false);
+ if (result)
+ return result;
+
+ if (is_lastmsg) {
+ /*
+ * It must generate STOP before read I2DR to prevent
+ * controller from generating another clock cycle
+ */
+ dev_dbg(dev, "<%s> clear MSTA\n", __func__);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
+ temp &= ~(I2CR_MSTA | I2CR_MTX);
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ if (!i2c_imx->stopped)
+ i2c_imx_bus_busy(i2c_imx, 0, false);
+ } else {
+ /*
+ * For i2c master receiver repeat restart operation like:
+ * read -> repeat MSTA -> read/write
+ * The controller must set MTX before read the last byte in
+ * the first read operation, otherwise the first read cost
+ * one extra clock cycle.
+ */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp |= I2CR_MTX;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
}
+ msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
- return IRQ_NONE;
+ return 0;
}
-static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
+static int i2c_imx_atomic_write(struct imx_i2c_struct *i2c_imx,
+ struct i2c_msg *msgs)
{
int i, result;
dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
- __func__, msgs->addr << 1);
+ __func__, i2c_8bit_addr_from_msg(msgs));
/* write slave address */
- writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
- result = i2c_imx_trx_complete(i2c_imx);
+ imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
+ result = i2c_imx_trx_complete(i2c_imx, true);
if (result)
return result;
result = i2c_imx_acked(i2c_imx);
@@ -342,8 +1365,8 @@ static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
dev_dbg(&i2c_imx->adapter.dev,
"<%s> write byte: B%d=0x%X\n",
__func__, i, msgs->buf[i]);
- writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
- result = i2c_imx_trx_complete(i2c_imx);
+ imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR);
+ result = i2c_imx_trx_complete(i2c_imx, true);
if (result)
return result;
result = i2c_imx_acked(i2c_imx);
@@ -353,59 +1376,108 @@ static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
return 0;
}
-static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
+static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
+{
+ dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
+ __func__, i2c_8bit_addr_from_msg(msgs));
+
+ i2c_imx->state = IMX_I2C_STATE_WRITE;
+ i2c_imx->msg = msgs;
+ i2c_imx->msg_buf_idx = 0;
+
+ /*
+ * By writing the device address we start the state machine in the ISR.
+ * The ISR will report when it is done or when it fails.
+ */
+ imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
+ wait_event_timeout(i2c_imx->queue,
+ i2c_imx->state == IMX_I2C_STATE_DONE ||
+ i2c_imx->state == IMX_I2C_STATE_FAILED,
+ (msgs->len + 1) * HZ / 10);
+ if (i2c_imx->state == IMX_I2C_STATE_FAILED) {
+ dev_dbg(&i2c_imx->adapter.dev, "<%s> write failed with %d\n",
+ __func__, i2c_imx->isr_result);
+ return i2c_imx->isr_result;
+ }
+ if (i2c_imx->state != IMX_I2C_STATE_DONE) {
+ dev_err(&i2c_imx->adapter.dev, "<%s> write timedout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ return 0;
+}
+
+static int i2c_imx_atomic_read(struct imx_i2c_struct *i2c_imx,
+ struct i2c_msg *msgs, bool is_lastmsg)
{
int i, result;
unsigned int temp;
+ int block_data = msgs->flags & I2C_M_RECV_LEN;
- dev_dbg(&i2c_imx->adapter.dev,
- "<%s> write slave address: addr=0x%x\n",
- __func__, (msgs->addr << 1) | 0x01);
-
- /* write slave address */
- writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
- result = i2c_imx_trx_complete(i2c_imx);
- if (result)
- return result;
- result = i2c_imx_acked(i2c_imx);
+ result = i2c_imx_prepare_read(i2c_imx, msgs, false);
if (result)
return result;
- dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
-
- /* setup bus to read data */
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
- temp &= ~I2CR_MTX;
- if (msgs->len - 1)
- temp &= ~I2CR_TXAK;
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
- readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
-
dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
/* read data */
for (i = 0; i < msgs->len; i++) {
- result = i2c_imx_trx_complete(i2c_imx);
+ u8 len = 0;
+
+ result = i2c_imx_trx_complete(i2c_imx, true);
if (result)
return result;
- if (i == (msgs->len - 1)) {
- /* It must generate STOP before read I2DR to prevent
- controller from generating another clock cycle */
+ /*
+ * First byte is the length of remaining packet
+ * in the SMBus block data read. Add it to
+ * msgs->len.
+ */
+ if ((!i) && block_data) {
+ len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
+ if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX))
+ return -EPROTO;
dev_dbg(&i2c_imx->adapter.dev,
- "<%s> clear MSTA\n", __func__);
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
- temp &= ~(I2CR_MSTA | I2CR_MTX);
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
- i2c_imx_bus_busy(i2c_imx, 0);
- i2c_imx->stopped = 1;
+ "<%s> read length: 0x%X\n",
+ __func__, len);
+ msgs->len += len;
+ }
+ if (i == (msgs->len - 1)) {
+ if (is_lastmsg) {
+ /*
+ * It must generate STOP before read I2DR to prevent
+ * controller from generating another clock cycle
+ */
+ dev_dbg(&i2c_imx->adapter.dev,
+ "<%s> clear MSTA\n", __func__);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
+ temp &= ~(I2CR_MSTA | I2CR_MTX);
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ if (!i2c_imx->stopped)
+ i2c_imx_bus_busy(i2c_imx, 0, true);
+ } else {
+ /*
+ * For i2c master receiver repeat restart operation like:
+ * read -> repeat MSTA -> read/write
+ * The controller must set MTX before read the last byte in
+ * the first read operation, otherwise the first read cost
+ * one extra clock cycle.
+ */
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ temp |= I2CR_MTX;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ }
} else if (i == (msgs->len - 2)) {
dev_dbg(&i2c_imx->adapter.dev,
"<%s> set TXAK\n", __func__);
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
temp |= I2CR_TXAK;
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
}
- msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
+ if ((!i) && block_data)
+ msgs->buf[0] = len;
+ else
+ msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
dev_dbg(&i2c_imx->adapter.dev,
"<%s> read byte: B%d=0x%X\n",
__func__, i, msgs->buf[i]);
@@ -413,29 +1485,85 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
return 0;
}
-static int i2c_imx_xfer(struct i2c_adapter *adapter,
- struct i2c_msg *msgs, int num)
+static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
+ bool is_lastmsg)
+{
+ int block_data = msgs->flags & I2C_M_RECV_LEN;
+
+ dev_dbg(&i2c_imx->adapter.dev,
+ "<%s> write slave address: addr=0x%x\n",
+ __func__, i2c_8bit_addr_from_msg(msgs));
+
+ i2c_imx->is_lastmsg = is_lastmsg;
+
+ if (block_data)
+ i2c_imx->state = IMX_I2C_STATE_READ_BLOCK_DATA;
+ else
+ i2c_imx->state = IMX_I2C_STATE_READ;
+ i2c_imx->msg = msgs;
+ i2c_imx->msg_buf_idx = 0;
+
+ /*
+ * By writing the device address we start the state machine in the ISR.
+ * The ISR will report when it is done or when it fails.
+ */
+ imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
+ wait_event_timeout(i2c_imx->queue,
+ i2c_imx->state == IMX_I2C_STATE_DONE ||
+ i2c_imx->state == IMX_I2C_STATE_FAILED,
+ (msgs->len + 1) * HZ / 10);
+ if (i2c_imx->state == IMX_I2C_STATE_FAILED) {
+ dev_dbg(&i2c_imx->adapter.dev, "<%s> read failed with %d\n",
+ __func__, i2c_imx->isr_result);
+ return i2c_imx->isr_result;
+ }
+ if (i2c_imx->state != IMX_I2C_STATE_DONE) {
+ dev_err(&i2c_imx->adapter.dev, "<%s> read timedout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ if (!i2c_imx->stopped)
+ return i2c_imx_bus_busy(i2c_imx, 0, false);
+
+ return 0;
+}
+
+static int i2c_imx_xfer_common(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs, int num, bool atomic)
{
unsigned int i, temp;
int result;
+ bool is_lastmsg = false;
struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
-
- dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
+ int use_dma = 0;
/* Start I2C transfer */
- result = i2c_imx_start(i2c_imx);
+ result = i2c_imx_start(i2c_imx, atomic);
+ if (result) {
+ /*
+ * Bus recovery uses gpiod_get_value_cansleep() which is not
+ * allowed within atomic context.
+ */
+ if (!atomic && i2c_imx->adapter.bus_recovery_info) {
+ i2c_recover_bus(&i2c_imx->adapter);
+ result = i2c_imx_start(i2c_imx, atomic);
+ }
+ }
+
if (result)
goto fail0;
/* read/write data */
for (i = 0; i < num; i++) {
+ if (i == num - 1)
+ is_lastmsg = true;
+
if (i) {
dev_dbg(&i2c_imx->adapter.dev,
"<%s> repeated start\n", __func__);
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
temp |= I2CR_RSTA;
- writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
- result = i2c_imx_bus_busy(i2c_imx, 1);
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+ result = i2c_imx_bus_busy(i2c_imx, 1, atomic);
if (result)
goto fail0;
}
@@ -443,107 +1571,178 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
"<%s> transfer message: %d\n", __func__, i);
/* write/read data */
#ifdef CONFIG_I2C_DEBUG_BUS
- temp = readb(i2c_imx->base + IMX_I2C_I2CR);
- dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
- "MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ dev_dbg(&i2c_imx->adapter.dev,
+ "<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
+ __func__,
(temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
(temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
(temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
- temp = readb(i2c_imx->base + IMX_I2C_I2SR);
+ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
dev_dbg(&i2c_imx->adapter.dev,
- "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
- "IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
+ "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
+ __func__,
(temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
(temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
(temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
(temp & I2SR_RXAK ? 1 : 0));
#endif
- if (msgs[i].flags & I2C_M_RD)
- result = i2c_imx_read(i2c_imx, &msgs[i]);
- else
- result = i2c_imx_write(i2c_imx, &msgs[i]);
+
+ use_dma = i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD &&
+ msgs[i].flags & I2C_M_DMA_SAFE;
+ if (msgs[i].flags & I2C_M_RD) {
+ int block_data = msgs->flags & I2C_M_RECV_LEN;
+
+ if (atomic)
+ result = i2c_imx_atomic_read(i2c_imx, &msgs[i], is_lastmsg);
+ else if (use_dma && !block_data)
+ result = i2c_imx_dma_read(i2c_imx, &msgs[i], is_lastmsg);
+ else
+ result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg);
+ } else {
+ if (atomic)
+ result = i2c_imx_atomic_write(i2c_imx, &msgs[i]);
+ else if (use_dma)
+ result = i2c_imx_dma_write(i2c_imx, &msgs[i]);
+ else
+ result = i2c_imx_write(i2c_imx, &msgs[i]);
+ }
if (result)
goto fail0;
}
fail0:
/* Stop I2C transfer */
- i2c_imx_stop(i2c_imx);
+ i2c_imx_stop(i2c_imx, atomic);
dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
(result < 0) ? "error" : "success msg",
(result < 0) ? result : num);
+ /* After data is transferred, switch to slave mode(as a receiver) */
+ if (i2c_imx->slave)
+ i2c_imx_slave_init(i2c_imx);
+
return (result < 0) ? result : num;
}
+static int i2c_imx_xfer(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs, int num)
+{
+ struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
+ int result;
+
+ result = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent);
+ if (result < 0)
+ return result;
+
+ result = i2c_imx_xfer_common(adapter, msgs, num, false);
+
+ pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent);
+
+ return result;
+}
+
+static int i2c_imx_xfer_atomic(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs, int num)
+{
+ struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
+ int result;
+
+ result = clk_enable(i2c_imx->clk);
+ if (result)
+ return result;
+
+ result = i2c_imx_xfer_common(adapter, msgs, num, true);
+
+ clk_disable(i2c_imx->clk);
+
+ return result;
+}
+
+/*
+ * We switch SCL and SDA to their GPIO function and do some bitbanging
+ * for bus recovery. These alternative pinmux settings can be
+ * described in the device tree by a separate pinctrl state "gpio". If
+ * this is missing this is not a big problem, the only implication is
+ * that we can't do bus recovery.
+ */
+static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
+ struct platform_device *pdev)
+{
+ struct i2c_bus_recovery_info *bri = &i2c_imx->rinfo;
+
+ bri->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (IS_ERR(bri->pinctrl))
+ return PTR_ERR(bri->pinctrl);
+
+ i2c_imx->adapter.bus_recovery_info = bri;
+
+ return 0;
+}
+
static u32 i2c_imx_func(struct i2c_adapter *adapter)
{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
+ | I2C_FUNC_SMBUS_READ_BLOCK_DATA;
}
-static struct i2c_algorithm i2c_imx_algo = {
- .master_xfer = i2c_imx_xfer,
- .functionality = i2c_imx_func,
+static const struct i2c_algorithm i2c_imx_algo = {
+ .xfer = i2c_imx_xfer,
+ .xfer_atomic = i2c_imx_xfer_atomic,
+ .functionality = i2c_imx_func,
+ .reg_slave = i2c_imx_reg_slave,
+ .unreg_slave = i2c_imx_unreg_slave,
};
-static int __init i2c_imx_probe(struct platform_device *pdev)
+static int i2c_imx_probe(struct platform_device *pdev)
{
- const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids,
- &pdev->dev);
struct imx_i2c_struct *i2c_imx;
struct resource *res;
- struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
+ struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
void __iomem *base;
int irq, ret;
- u32 bitrate;
-
- dev_dbg(&pdev->dev, "<%s>\n", __func__);
+ dma_addr_t phy_addr;
+ const struct imx_i2c_hwdata *match;
irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(&pdev->dev, "can't get irq number\n");
- return -ENOENT;
- }
+ if (irq < 0)
+ return dev_err_probe(&pdev->dev, irq, "can't get IRQ\n");
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- base = devm_ioremap_resource(&pdev->dev, res);
+ base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(base))
- return PTR_ERR(base);
+ return dev_err_probe(&pdev->dev, PTR_ERR(base), "can't get IO memory\n");
- i2c_imx = devm_kzalloc(&pdev->dev, sizeof(struct imx_i2c_struct),
- GFP_KERNEL);
- if (!i2c_imx) {
- dev_err(&pdev->dev, "can't allocate interface\n");
+ phy_addr = (dma_addr_t)res->start;
+ i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL);
+ if (!i2c_imx)
return -ENOMEM;
- }
- if (of_id)
- pdev->id_entry = of_id->data;
- i2c_imx->devtype = pdev->id_entry->driver_data;
+ spin_lock_init(&i2c_imx->slave_lock);
+ hrtimer_setup(&i2c_imx->slave_timer, i2c_imx_slave_timeout, CLOCK_MONOTONIC,
+ HRTIMER_MODE_ABS);
+
+ match = device_get_match_data(&pdev->dev);
+ if (match)
+ i2c_imx->hwdata = match;
+ else
+ i2c_imx->hwdata = (struct imx_i2c_hwdata *)
+ platform_get_device_id(pdev)->driver_data;
/* Setup i2c_imx driver structure */
- strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
+ strscpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
i2c_imx->adapter.owner = THIS_MODULE;
i2c_imx->adapter.algo = &i2c_imx_algo;
i2c_imx->adapter.dev.parent = &pdev->dev;
- i2c_imx->adapter.nr = pdev->id;
+ i2c_imx->adapter.nr = pdev->id;
i2c_imx->adapter.dev.of_node = pdev->dev.of_node;
i2c_imx->base = base;
+ ACPI_COMPANION_SET(&i2c_imx->adapter.dev, ACPI_COMPANION(&pdev->dev));
/* Get I2C clock */
- i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(i2c_imx->clk)) {
- dev_err(&pdev->dev, "can't get I2C clock\n");
- return PTR_ERR(i2c_imx->clk);
- }
-
- /* Request IRQ */
- ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
- pdev->name, i2c_imx);
- if (ret) {
- dev_err(&pdev->dev, "can't claim irq %d\n", irq);
- return ret;
- }
+ i2c_imx->clk = devm_clk_get_enabled(&pdev->dev, NULL);
+ if (IS_ERR(i2c_imx->clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(i2c_imx->clk),
+ "can't get I2C clock\n");
/* Init queue */
init_waitqueue_head(&i2c_imx->queue);
@@ -551,72 +1750,209 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
/* Set up adapter data */
i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
+ /* Set up platform driver data */
+ platform_set_drvdata(pdev, i2c_imx);
+
+ pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret < 0)
+ goto rpm_disable;
+
+ /* Request IRQ */
+ ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED | IRQF_NO_SUSPEND,
+ pdev->name, i2c_imx);
+ if (ret) {
+ dev_err(&pdev->dev, "can't claim irq %d\n", irq);
+ goto rpm_disable;
+ }
+
+ /*
+ * We use the single-master property for backward compatibility.
+ * By default multi master mode is enabled.
+ */
+ i2c_imx->multi_master = !of_property_read_bool(pdev->dev.of_node, "single-master");
+
/* Set up clock divider */
- bitrate = IMX_I2C_BIT_RATE;
+ i2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
ret = of_property_read_u32(pdev->dev.of_node,
- "clock-frequency", &bitrate);
+ "clock-frequency", &i2c_imx->bitrate);
if (ret < 0 && pdata && pdata->bitrate)
- bitrate = pdata->bitrate;
- i2c_imx_set_clk(i2c_imx, bitrate);
+ i2c_imx->bitrate = pdata->bitrate;
+ i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call;
+ clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb);
+ ret = i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
+ if (ret < 0) {
+ dev_err(&pdev->dev, "can't get I2C clock\n");
+ goto clk_notifier_unregister;
+ }
- /* Set up chip registers to defaults */
- writeb(0, i2c_imx->base + IMX_I2C_I2CR);
- writeb(0, i2c_imx->base + IMX_I2C_I2SR);
+ i2c_imx_reset_regs(i2c_imx);
- /* Add I2C adapter */
- ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
- if (ret < 0) {
- dev_err(&pdev->dev, "registration failed\n");
- return ret;
+ /* Init optional bus recovery function */
+ ret = i2c_imx_init_recovery_info(i2c_imx, pdev);
+ /* Give it another chance if pinctrl used is not ready yet */
+ if (ret == -EPROBE_DEFER)
+ goto clk_notifier_unregister;
+
+ /*
+ * DMA mode should be optional for I2C, when encountering DMA errors,
+ * no need to exit I2C probe. Only print warning to show DMA error and
+ * use PIO mode directly to ensure I2C bus available as much as possible.
+ */
+ ret = i2c_imx_dma_request(i2c_imx, phy_addr);
+ if (ret) {
+ if (ret == -EPROBE_DEFER) {
+ dev_err_probe(&pdev->dev, ret, "can't get DMA channels\n");
+ goto clk_notifier_unregister;
+ } else if (ret == -ENODEV) {
+ dev_dbg(&pdev->dev, "Only use PIO mode\n");
+ } else {
+ dev_warn(&pdev->dev, "Failed to setup DMA (%pe), only use PIO mode\n",
+ ERR_PTR(ret));
+ }
}
- of_i2c_register_devices(&i2c_imx->adapter);
+ /* Add I2C adapter */
+ ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
+ if (ret < 0)
+ goto clk_notifier_unregister;
- /* Set up platform driver data */
- platform_set_drvdata(pdev, i2c_imx);
+ pm_runtime_put_autosuspend(&pdev->dev);
dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
- dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
- res->start, res->end);
- dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x\n",
- resource_size(res), res->start);
+ dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
i2c_imx->adapter.name);
dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
return 0; /* Return OK */
+
+clk_notifier_unregister:
+ clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
+ free_irq(irq, i2c_imx);
+rpm_disable:
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ return ret;
}
-static int __exit i2c_imx_remove(struct platform_device *pdev)
+static void i2c_imx_remove(struct platform_device *pdev)
{
struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
+ int irq, ret;
+
+ ret = pm_runtime_get_sync(&pdev->dev);
+
+ hrtimer_cancel(&i2c_imx->slave_timer);
/* remove adapter */
dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
i2c_del_adapter(&i2c_imx->adapter);
- /* setup chip registers to defaults */
- writeb(0, i2c_imx->base + IMX_I2C_IADR);
- writeb(0, i2c_imx->base + IMX_I2C_IFDR);
- writeb(0, i2c_imx->base + IMX_I2C_I2CR);
- writeb(0, i2c_imx->base + IMX_I2C_I2SR);
+ if (i2c_imx->dma)
+ i2c_imx_dma_free(i2c_imx);
+
+ if (ret >= 0) {
+ /* setup chip registers to defaults */
+ imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
+ imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR);
+ imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
+ imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
+ }
+
+ clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
+ irq = platform_get_irq(pdev, 0);
+ if (irq >= 0)
+ free_irq(irq, i2c_imx);
+
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+}
+
+static int i2c_imx_runtime_suspend(struct device *dev)
+{
+ struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
+
+ clk_disable(i2c_imx->clk);
+ return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int i2c_imx_runtime_resume(struct device *dev)
+{
+ struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
+ int ret;
+
+ ret = pinctrl_pm_select_default_state(dev);
+ if (ret)
+ return ret;
+
+ ret = clk_enable(i2c_imx->clk);
+ if (ret)
+ dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);
+
+ return ret;
+}
+
+static int i2c_imx_suspend(struct device *dev)
+{
+ /*
+ * Some I2C devices may need the I2C controller to remain active
+ * during resume_noirq() or suspend_noirq(). If the controller is
+ * autosuspended, there is no way to wake it up once runtime PM is
+ * disabled (in suspend_late()).
+ *
+ * During system resume, the I2C controller will be available only
+ * after runtime PM is re-enabled (in resume_early()). However, this
+ * may be too late for some devices.
+ *
+ * Wake up the controller in the suspend() callback while runtime PM
+ * is still enabled. The I2C controller will remain available until
+ * the suspend_noirq() callback (pm_runtime_force_suspend()) is
+ * called. During resume, the I2C controller can be restored by the
+ * resume_noirq() callback (pm_runtime_force_resume()).
+ *
+ * Finally, the resume() callback re-enables autosuspend, ensuring
+ * the I2C controller remains available until the system enters
+ * suspend_noirq() and from resume_noirq().
+ */
+ return pm_runtime_resume_and_get(dev);
+}
+
+static int i2c_imx_resume(struct device *dev)
+{
+ pm_runtime_put_autosuspend(dev);
return 0;
}
+static const struct dev_pm_ops i2c_imx_pm_ops = {
+ NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SYSTEM_SLEEP_PM_OPS(i2c_imx_suspend, i2c_imx_resume)
+ RUNTIME_PM_OPS(i2c_imx_runtime_suspend, i2c_imx_runtime_resume, NULL)
+};
+
static struct platform_driver i2c_imx_driver = {
- .remove = __exit_p(i2c_imx_remove),
- .driver = {
- .name = DRIVER_NAME,
- .owner = THIS_MODULE,
+ .probe = i2c_imx_probe,
+ .remove = i2c_imx_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .pm = pm_ptr(&i2c_imx_pm_ops),
.of_match_table = i2c_imx_dt_ids,
+ .acpi_match_table = i2c_imx_acpi_ids,
},
- .id_table = imx_i2c_devtype,
+ .id_table = imx_i2c_devtype,
};
static int __init i2c_adap_imx_init(void)
{
- return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe);
+ return platform_driver_register(&i2c_imx_driver);
}
subsys_initcall(i2c_adap_imx_init);