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Diffstat (limited to 'drivers/i2c/busses/i2c-rcar.c')
-rw-r--r--drivers/i2c/busses/i2c-rcar.c804
1 files changed, 531 insertions, 273 deletions
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index 254e6219e538..d51884ab99f4 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -2,8 +2,8 @@
/*
* Driver for the Renesas R-Car I2C unit
*
- * Copyright (C) 2014-15 Wolfram Sang <wsa@sang-engineering.com>
- * Copyright (C) 2011-2015 Renesas Electronics Corporation
+ * Copyright (C) 2014-19 Wolfram Sang <wsa@sang-engineering.com>
+ * Copyright (C) 2011-2019 Renesas Electronics Corporation
*
* Copyright (C) 2012-14 Renesas Solutions Corp.
* Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
@@ -19,10 +19,12 @@
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/of_device.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
@@ -39,84 +41,106 @@
#define ICSAR 0x1C /* slave address */
#define ICMAR 0x20 /* master address */
#define ICRXTX 0x24 /* data port */
-#define ICDMAER 0x3c /* DMA enable */
-#define ICFBSCR 0x38 /* first bit setup cycle */
+#define ICCCR2 0x28 /* Clock control 2 */
+#define ICMPR 0x2C /* SCL mask control */
+#define ICHPR 0x30 /* SCL HIGH control */
+#define ICLPR 0x34 /* SCL LOW control */
+#define ICFBSCR 0x38 /* first bit setup cycle (Gen3) */
+#define ICDMAER 0x3c /* DMA enable (Gen3) */
/* ICSCR */
-#define SDBS (1 << 3) /* slave data buffer select */
-#define SIE (1 << 2) /* slave interface enable */
-#define GCAE (1 << 1) /* general call address enable */
-#define FNA (1 << 0) /* forced non acknowledgment */
+#define SDBS BIT(3) /* slave data buffer select */
+#define SIE BIT(2) /* slave interface enable */
+#define GCAE BIT(1) /* general call address enable */
+#define FNA BIT(0) /* forced non acknowledgment */
/* ICMCR */
-#define MDBS (1 << 7) /* non-fifo mode switch */
-#define FSCL (1 << 6) /* override SCL pin */
-#define FSDA (1 << 5) /* override SDA pin */
-#define OBPC (1 << 4) /* override pins */
-#define MIE (1 << 3) /* master if enable */
-#define TSBE (1 << 2)
-#define FSB (1 << 1) /* force stop bit */
-#define ESG (1 << 0) /* enable start bit gen */
+#define MDBS BIT(7) /* non-fifo mode switch */
+#define FSCL BIT(6) /* override SCL pin */
+#define FSDA BIT(5) /* override SDA pin */
+#define OBPC BIT(4) /* override pins */
+#define MIE BIT(3) /* master if enable */
+#define TSBE BIT(2)
+#define FSB BIT(1) /* force stop bit */
+#define ESG BIT(0) /* enable start bit gen */
/* ICSSR (also for ICSIER) */
-#define GCAR (1 << 6) /* general call received */
-#define STM (1 << 5) /* slave transmit mode */
-#define SSR (1 << 4) /* stop received */
-#define SDE (1 << 3) /* slave data empty */
-#define SDT (1 << 2) /* slave data transmitted */
-#define SDR (1 << 1) /* slave data received */
-#define SAR (1 << 0) /* slave addr received */
+#define GCAR BIT(6) /* general call received */
+#define STM BIT(5) /* slave transmit mode */
+#define SSR BIT(4) /* stop received */
+#define SDE BIT(3) /* slave data empty */
+#define SDT BIT(2) /* slave data transmitted */
+#define SDR BIT(1) /* slave data received */
+#define SAR BIT(0) /* slave addr received */
/* ICMSR (also for ICMIE) */
-#define MNR (1 << 6) /* nack received */
-#define MAL (1 << 5) /* arbitration lost */
-#define MST (1 << 4) /* sent a stop */
-#define MDE (1 << 3)
-#define MDT (1 << 2)
-#define MDR (1 << 1)
-#define MAT (1 << 0) /* slave addr xfer done */
+#define MNR BIT(6) /* nack received */
+#define MAL BIT(5) /* arbitration lost */
+#define MST BIT(4) /* sent a stop */
+#define MDE BIT(3)
+#define MDT BIT(2)
+#define MDR BIT(1)
+#define MAT BIT(0) /* slave addr xfer done */
/* ICDMAER */
-#define RSDMAE (1 << 3) /* DMA Slave Received Enable */
-#define TSDMAE (1 << 2) /* DMA Slave Transmitted Enable */
-#define RMDMAE (1 << 1) /* DMA Master Received Enable */
-#define TMDMAE (1 << 0) /* DMA Master Transmitted Enable */
+#define RSDMAE BIT(3) /* DMA Slave Received Enable */
+#define TSDMAE BIT(2) /* DMA Slave Transmitted Enable */
+#define RMDMAE BIT(1) /* DMA Master Received Enable */
+#define TMDMAE BIT(0) /* DMA Master Transmitted Enable */
+
+/* ICCCR2 */
+#define FMPE BIT(7) /* Fast Mode Plus Enable */
+#define CDFD BIT(2) /* CDF Disable */
+#define HLSE BIT(1) /* HIGH/LOW Separate Control Enable */
+#define SME BIT(0) /* SCL Mask Enable */
/* ICFBSCR */
-#define TCYC06 0x04 /* 6*Tcyc delay 1st bit between SDA and SCL */
#define TCYC17 0x0f /* 17*Tcyc delay 1st bit between SDA and SCL */
+#define RCAR_MIN_DMA_LEN 8
+
+/* SCL low/high ratio 5:4 to meet all I2C timing specs (incl safety margin) */
+#define RCAR_SCLD_RATIO 5
+#define RCAR_SCHD_RATIO 4
+/*
+ * SMD should be smaller than SCLD/SCHD and is always around 20 in the docs.
+ * Thus, we simply use 20 which works for low and high speeds.
+ */
+#define RCAR_DEFAULT_SMD 20
#define RCAR_BUS_PHASE_START (MDBS | MIE | ESG)
#define RCAR_BUS_PHASE_DATA (MDBS | MIE)
-#define RCAR_BUS_MASK_DATA (~(ESG | FSB) & 0xFF)
#define RCAR_BUS_PHASE_STOP (MDBS | MIE | FSB)
#define RCAR_IRQ_SEND (MNR | MAL | MST | MAT | MDE)
#define RCAR_IRQ_RECV (MNR | MAL | MST | MAT | MDR)
#define RCAR_IRQ_STOP (MST)
-#define RCAR_IRQ_ACK_SEND (~(MAT | MDE) & 0x7F)
-#define RCAR_IRQ_ACK_RECV (~(MAT | MDR) & 0x7F)
-
-#define ID_LAST_MSG (1 << 0)
-#define ID_FIRST_MSG (1 << 1)
-#define ID_DONE (1 << 2)
-#define ID_ARBLOST (1 << 3)
-#define ID_NACK (1 << 4)
+#define ID_LAST_MSG BIT(0)
+#define ID_REP_AFTER_RD BIT(1)
+#define ID_DONE BIT(2)
+#define ID_ARBLOST BIT(3)
+#define ID_NACK BIT(4)
+#define ID_EPROTO BIT(5)
/* persistent flags */
-#define ID_P_REP_AFTER_RD BIT(29)
+#define ID_P_FMPLUS BIT(27)
+#define ID_P_NOT_ATOMIC BIT(28)
+#define ID_P_HOST_NOTIFY BIT(29)
#define ID_P_NO_RXDMA BIT(30) /* HW forbids RXDMA sometimes */
#define ID_P_PM_BLOCKED BIT(31)
-#define ID_P_MASK GENMASK(31, 29)
+#define ID_P_MASK GENMASK(31, 27)
+
+#define ID_SLAVE_NACK BIT(0)
enum rcar_i2c_type {
I2C_RCAR_GEN1,
I2C_RCAR_GEN2,
I2C_RCAR_GEN3,
+ I2C_RCAR_GEN4,
};
struct rcar_i2c_priv {
+ u32 flags;
void __iomem *io;
struct i2c_adapter adap;
struct i2c_msg *msg;
@@ -127,7 +151,9 @@ struct rcar_i2c_priv {
int pos;
u32 icccr;
- u32 flags;
+ u16 schd;
+ u16 scld;
+ u8 smd;
u8 recovery_icmcr; /* protected by adapter lock */
enum rcar_i2c_type devtype;
struct i2c_client *slave;
@@ -139,14 +165,15 @@ struct rcar_i2c_priv {
enum dma_data_direction dma_direction;
struct reset_control *rstc;
+ int irq;
+
+ struct i2c_client *host_notify_client;
+ u8 slave_flags;
};
#define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent)
#define rcar_i2c_is_recv(p) ((p)->msg->flags & I2C_M_RD)
-#define LOOP_TIMEOUT 1024
-
-
static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val)
{
writel(val, priv->io + reg);
@@ -157,13 +184,17 @@ static u32 rcar_i2c_read(struct rcar_i2c_priv *priv, int reg)
return readl(priv->io + reg);
}
+static void rcar_i2c_clear_irq(struct rcar_i2c_priv *priv, u32 val)
+{
+ writel(~val & 0x7f, priv->io + ICMSR);
+}
+
static int rcar_i2c_get_scl(struct i2c_adapter *adap)
{
struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
return !!(rcar_i2c_read(priv, ICMCR) & FSCL);
-
-};
+}
static void rcar_i2c_set_scl(struct i2c_adapter *adap, int val)
{
@@ -175,7 +206,7 @@ static void rcar_i2c_set_scl(struct i2c_adapter *adap, int val)
priv->recovery_icmcr &= ~FSCL;
rcar_i2c_write(priv, ICMCR, priv->recovery_icmcr);
-};
+}
static void rcar_i2c_set_sda(struct i2c_adapter *adap, int val)
{
@@ -187,15 +218,14 @@ static void rcar_i2c_set_sda(struct i2c_adapter *adap, int val)
priv->recovery_icmcr &= ~FSDA;
rcar_i2c_write(priv, ICMCR, priv->recovery_icmcr);
-};
+}
static int rcar_i2c_get_bus_free(struct i2c_adapter *adap)
{
struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
return !(rcar_i2c_read(priv, ICMCR) & FSDA);
-
-};
+}
static struct i2c_bus_recovery_info rcar_i2c_bri = {
.get_scl = rcar_i2c_get_scl,
@@ -204,6 +234,7 @@ static struct i2c_bus_recovery_info rcar_i2c_bri = {
.get_bus_free = rcar_i2c_get_bus_free,
.recover_bus = i2c_generic_scl_recovery,
};
+
static void rcar_i2c_init(struct rcar_i2c_priv *priv)
{
/* reset master mode */
@@ -211,58 +242,74 @@ static void rcar_i2c_init(struct rcar_i2c_priv *priv)
rcar_i2c_write(priv, ICMCR, MDBS);
rcar_i2c_write(priv, ICMSR, 0);
/* start clock */
- rcar_i2c_write(priv, ICCCR, priv->icccr);
+ if (priv->devtype < I2C_RCAR_GEN3) {
+ rcar_i2c_write(priv, ICCCR, priv->icccr);
+ } else {
+ u32 icccr2 = CDFD | HLSE | SME;
+
+ if (priv->flags & ID_P_FMPLUS)
+ icccr2 |= FMPE;
+
+ rcar_i2c_write(priv, ICCCR2, icccr2);
+ rcar_i2c_write(priv, ICCCR, priv->icccr);
+ rcar_i2c_write(priv, ICMPR, priv->smd);
+ rcar_i2c_write(priv, ICHPR, priv->schd);
+ rcar_i2c_write(priv, ICLPR, priv->scld);
+ rcar_i2c_write(priv, ICFBSCR, TCYC17);
+ }
+}
+
+static void rcar_i2c_reset_slave(struct rcar_i2c_priv *priv)
+{
+ rcar_i2c_write(priv, ICSIER, 0);
+ rcar_i2c_write(priv, ICSSR, 0);
+ rcar_i2c_write(priv, ICSCR, SDBS);
+ rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */
}
static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
{
- int i;
+ int ret;
+ u32 val;
- for (i = 0; i < LOOP_TIMEOUT; i++) {
- /* make sure that bus is not busy */
- if (!(rcar_i2c_read(priv, ICMCR) & FSDA))
- return 0;
- udelay(1);
+ ret = readl_poll_timeout(priv->io + ICMCR, val, !(val & FSDA), 10,
+ priv->adap.timeout);
+ if (ret) {
+ /* Waiting did not help, try to recover */
+ priv->recovery_icmcr = MDBS | OBPC | FSDA | FSCL;
+ ret = i2c_recover_bus(&priv->adap);
}
- /* Waiting did not help, try to recover */
- priv->recovery_icmcr = MDBS | OBPC | FSDA | FSCL;
- return i2c_recover_bus(&priv->adap);
+ return ret;
}
-static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv, struct i2c_timings *t)
+static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv)
{
- u32 scgd, cdf, round, ick, sum, scl, cdf_width;
+ u32 cdf, round, ick, sum, scl, cdf_width;
unsigned long rate;
struct device *dev = rcar_i2c_priv_to_dev(priv);
+ struct i2c_timings t = {
+ .bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ,
+ .scl_fall_ns = 35,
+ .scl_rise_ns = 200,
+ .scl_int_delay_ns = 50,
+ };
/* Fall back to previously used values if not supplied */
- t->bus_freq_hz = t->bus_freq_hz ?: 100000;
- t->scl_fall_ns = t->scl_fall_ns ?: 35;
- t->scl_rise_ns = t->scl_rise_ns ?: 200;
- t->scl_int_delay_ns = t->scl_int_delay_ns ?: 50;
-
- switch (priv->devtype) {
- case I2C_RCAR_GEN1:
- cdf_width = 2;
- break;
- case I2C_RCAR_GEN2:
- case I2C_RCAR_GEN3:
- cdf_width = 3;
- break;
- default:
- dev_err(dev, "device type error\n");
- return -EIO;
- }
+ i2c_parse_fw_timings(dev, &t, false);
+ priv->smd = RCAR_DEFAULT_SMD;
/*
* calculate SCL clock
* see
- * ICCCR
+ * ICCCR (and ICCCR2 for Gen3+)
*
* ick = clkp / (1 + CDF)
* SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
*
+ * for Gen3+:
+ * SCL = clkp / (8 + SMD * 2 + SCLD + SCHD +F[(ticf + tr + intd) * clkp])
+ *
* ick : I2C internal clock < 20 MHz
* ticf : I2C SCL falling time
* tr : I2C SCL rising time
@@ -272,124 +319,152 @@ static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv, struct i2c_timin
*/
rate = clk_get_rate(priv->clk);
cdf = rate / 20000000;
- if (cdf >= 1U << cdf_width) {
- dev_err(dev, "Input clock %lu too high\n", rate);
- return -EIO;
- }
- ick = rate / (cdf + 1);
+ cdf_width = (priv->devtype == I2C_RCAR_GEN1) ? 2 : 3;
+ if (cdf >= 1U << cdf_width)
+ goto err_no_val;
+
+ if (t.bus_freq_hz > I2C_MAX_FAST_MODE_FREQ && priv->devtype >= I2C_RCAR_GEN4)
+ priv->flags |= ID_P_FMPLUS;
+ else
+ priv->flags &= ~ID_P_FMPLUS;
+
+ /* On Gen3+, we use cdf only for the filters, not as a SCL divider */
+ ick = rate / (priv->devtype < I2C_RCAR_GEN3 ? (cdf + 1) : 1);
/*
- * it is impossible to calculate large scale
- * number on u32. separate it
+ * It is impossible to calculate a large scale number on u32. Separate it.
*
* F[(ticf + tr + intd) * ick] with sum = (ticf + tr + intd)
* = F[sum * ick / 1000000000]
* = F[(ick / 1000000) * sum / 1000]
*/
- sum = t->scl_fall_ns + t->scl_rise_ns + t->scl_int_delay_ns;
- round = (ick + 500000) / 1000000 * sum;
- round = (round + 500) / 1000;
+ sum = t.scl_fall_ns + t.scl_rise_ns + t.scl_int_delay_ns;
+ round = DIV_ROUND_CLOSEST(ick, 1000000);
+ round = DIV_ROUND_CLOSEST(round * sum, 1000);
- /*
- * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
- *
- * Calculation result (= SCL) should be less than
- * bus_speed for hardware safety
- *
- * We could use something along the lines of
- * div = ick / (bus_speed + 1) + 1;
- * scgd = (div - 20 - round + 7) / 8;
- * scl = ick / (20 + (scgd * 8) + round);
- * (not fully verified) but that would get pretty involved
- */
- for (scgd = 0; scgd < 0x40; scgd++) {
- scl = ick / (20 + (scgd * 8) + round);
- if (scl <= t->bus_freq_hz)
- goto scgd_find;
- }
- dev_err(dev, "it is impossible to calculate best SCL\n");
- return -EIO;
+ if (priv->devtype < I2C_RCAR_GEN3) {
+ u32 scgd;
+ /*
+ * SCL = ick / (20 + 8 * SCGD + F[(ticf + tr + intd) * ick])
+ * 20 + 8 * SCGD + F[...] = ick / SCL
+ * SCGD = ((ick / SCL) - 20 - F[...]) / 8
+ * Result (= SCL) should be less than bus_speed for hardware safety
+ */
+ scgd = DIV_ROUND_UP(ick, t.bus_freq_hz ?: 1);
+ scgd = DIV_ROUND_UP(scgd - 20 - round, 8);
+ scl = ick / (20 + 8 * scgd + round);
+
+ if (scgd > 0x3f)
+ goto err_no_val;
+
+ dev_dbg(dev, "clk %u/%u(%lu), round %u, CDF: %u, SCGD: %u\n",
+ scl, t.bus_freq_hz, rate, round, cdf, scgd);
+
+ priv->icccr = scgd << cdf_width | cdf;
+ } else {
+ u32 x, sum_ratio = RCAR_SCHD_RATIO + RCAR_SCLD_RATIO;
+ /*
+ * SCLD/SCHD ratio and SMD default value are explained above
+ * where they are defined. With these definitions, we can compute
+ * x as a base value for the SCLD/SCHD ratio:
+ *
+ * SCL = clkp / (8 + 2 * SMD + SCLD + SCHD + F[(ticf + tr + intd) * clkp])
+ * SCL = clkp / (8 + 2 * SMD + RCAR_SCLD_RATIO * x
+ * + RCAR_SCHD_RATIO * x + F[...])
+ *
+ * with: sum_ratio = RCAR_SCLD_RATIO + RCAR_SCHD_RATIO
+ *
+ * SCL = clkp / (8 + 2 * smd + sum_ratio * x + F[...])
+ * 8 + 2 * smd + sum_ratio * x + F[...] = clkp / SCL
+ * x = ((clkp / SCL) - 8 - 2 * smd - F[...]) / sum_ratio
+ */
+ x = DIV_ROUND_UP(rate, t.bus_freq_hz ?: 1);
+ x = DIV_ROUND_UP(x - 8 - 2 * priv->smd - round, sum_ratio);
+ scl = rate / (8 + 2 * priv->smd + sum_ratio * x + round);
-scgd_find:
- dev_dbg(dev, "clk %d/%d(%lu), round %u, CDF:0x%x, SCGD: 0x%x\n",
- scl, t->bus_freq_hz, clk_get_rate(priv->clk), round, cdf, scgd);
+ if (x == 0 || x * RCAR_SCLD_RATIO > 0xffff)
+ goto err_no_val;
- /* keep icccr value */
- priv->icccr = scgd << cdf_width | cdf;
+ priv->icccr = cdf;
+ priv->schd = RCAR_SCHD_RATIO * x;
+ priv->scld = RCAR_SCLD_RATIO * x;
+ if (priv->smd >= priv->schd)
+ priv->smd = priv->schd - 1;
+
+ dev_dbg(dev, "clk %u/%u(%lu), round %u, CDF: %u SCHD %u SCLD %u SMD %u\n",
+ scl, t.bus_freq_hz, rate, round, cdf, priv->schd, priv->scld, priv->smd);
+ }
return 0;
+
+err_no_val:
+ dev_err(dev, "it is impossible to calculate best SCL\n");
+ return -EINVAL;
}
+/*
+ * We don't have a test case but the HW engineers say that the write order of
+ * ICMSR and ICMCR depends on whether we issue START or REP_START. So, ICMSR
+ * handling is outside of this function. First messages clear ICMSR before this
+ * function, interrupt handlers clear the relevant bits after this function.
+ */
static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
{
int read = !!rcar_i2c_is_recv(priv);
+ bool rep_start = !(priv->flags & ID_REP_AFTER_RD);
priv->pos = 0;
+ priv->flags &= ID_P_MASK;
+
if (priv->msgs_left == 1)
priv->flags |= ID_LAST_MSG;
rcar_i2c_write(priv, ICMAR, i2c_8bit_addr_from_msg(priv->msg));
- /*
- * We don't have a test case but the HW engineers say that the write order
- * of ICMSR and ICMCR depends on whether we issue START or REP_START. Since
- * it didn't cause a drawback for me, let's rather be safe than sorry.
- */
- if (priv->flags & ID_FIRST_MSG) {
- rcar_i2c_write(priv, ICMSR, 0);
+ if (priv->flags & ID_P_NOT_ATOMIC)
+ rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
+
+ if (rep_start)
rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);
- } else {
- if (priv->flags & ID_P_REP_AFTER_RD)
- priv->flags &= ~ID_P_REP_AFTER_RD;
- else
- rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);
- rcar_i2c_write(priv, ICMSR, 0);
- }
- rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
+}
+
+static void rcar_i2c_first_msg(struct rcar_i2c_priv *priv,
+ struct i2c_msg *msgs, int num)
+{
+ priv->msg = msgs;
+ priv->msgs_left = num;
+ rcar_i2c_write(priv, ICMSR, 0); /* must be before preparing msg */
+ rcar_i2c_prepare_msg(priv);
}
static void rcar_i2c_next_msg(struct rcar_i2c_priv *priv)
{
priv->msg++;
priv->msgs_left--;
- priv->flags &= ID_P_MASK;
rcar_i2c_prepare_msg(priv);
+ /* ICMSR handling must come afterwards in the irq handler */
}
-/*
- * interrupt functions
- */
-static void rcar_i2c_dma_unmap(struct rcar_i2c_priv *priv)
+static void rcar_i2c_cleanup_dma(struct rcar_i2c_priv *priv, bool terminate)
{
struct dma_chan *chan = priv->dma_direction == DMA_FROM_DEVICE
? priv->dma_rx : priv->dma_tx;
- /* Disable DMA Master Received/Transmitted */
- rcar_i2c_write(priv, ICDMAER, 0);
-
- /* Reset default delay */
- rcar_i2c_write(priv, ICFBSCR, TCYC06);
+ /* only allowed from thread context! */
+ if (terminate)
+ dmaengine_terminate_sync(chan);
dma_unmap_single(chan->device->dev, sg_dma_address(&priv->sg),
sg_dma_len(&priv->sg), priv->dma_direction);
- /* Gen3 can only do one RXDMA per transfer and we just completed it */
- if (priv->devtype == I2C_RCAR_GEN3 &&
+ /* Gen3+ can only do one RXDMA per transfer and we just completed it */
+ if (priv->devtype >= I2C_RCAR_GEN3 &&
priv->dma_direction == DMA_FROM_DEVICE)
priv->flags |= ID_P_NO_RXDMA;
priv->dma_direction = DMA_NONE;
-}
-
-static void rcar_i2c_cleanup_dma(struct rcar_i2c_priv *priv)
-{
- if (priv->dma_direction == DMA_NONE)
- return;
- else if (priv->dma_direction == DMA_FROM_DEVICE)
- dmaengine_terminate_all(priv->dma_rx);
- else if (priv->dma_direction == DMA_TO_DEVICE)
- dmaengine_terminate_all(priv->dma_tx);
- rcar_i2c_dma_unmap(priv);
+ /* Disable DMA Master Received/Transmitted, must be last! */
+ rcar_i2c_write(priv, ICDMAER, 0);
}
static void rcar_i2c_dma_callback(void *data)
@@ -398,10 +473,10 @@ static void rcar_i2c_dma_callback(void *data)
priv->pos += sg_dma_len(&priv->sg);
- rcar_i2c_dma_unmap(priv);
+ rcar_i2c_cleanup_dma(priv, false);
}
-static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
+static bool rcar_i2c_dma(struct rcar_i2c_priv *priv)
{
struct device *dev = rcar_i2c_priv_to_dev(priv);
struct i2c_msg *msg = priv->msg;
@@ -415,9 +490,9 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
int len;
/* Do various checks to see if DMA is feasible at all */
- if (IS_ERR(chan) || msg->len < 8 || !(msg->flags & I2C_M_DMA_SAFE) ||
- (read && priv->flags & ID_P_NO_RXDMA))
- return;
+ if (!(priv->flags & ID_P_NOT_ATOMIC) || IS_ERR(chan) || msg->len < RCAR_MIN_DMA_LEN ||
+ !(msg->flags & I2C_M_DMA_SAFE) || (read && priv->flags & ID_P_NO_RXDMA))
+ return false;
if (read) {
/*
@@ -437,7 +512,7 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
dma_addr = dma_map_single(chan->device->dev, buf, len, dir);
if (dma_mapping_error(chan->device->dev, dma_addr)) {
dev_dbg(dev, "dma map failed, using PIO\n");
- return;
+ return false;
}
sg_dma_len(&priv->sg) = len;
@@ -450,8 +525,8 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!txdesc) {
dev_dbg(dev, "dma prep slave sg failed, using PIO\n");
- rcar_i2c_cleanup_dma(priv);
- return;
+ rcar_i2c_cleanup_dma(priv, false);
+ return false;
}
txdesc->callback = rcar_i2c_dma_callback;
@@ -460,13 +535,10 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
cookie = dmaengine_submit(txdesc);
if (dma_submit_error(cookie)) {
dev_dbg(dev, "submitting dma failed, using PIO\n");
- rcar_i2c_cleanup_dma(priv);
- return;
+ rcar_i2c_cleanup_dma(priv, false);
+ return false;
}
- /* Set delay for DMA operations */
- rcar_i2c_write(priv, ICFBSCR, TCYC17);
-
/* Enable DMA Master Received/Transmitted */
if (read)
rcar_i2c_write(priv, ICDMAER, RMDMAE);
@@ -474,14 +546,23 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
rcar_i2c_write(priv, ICDMAER, TMDMAE);
dma_async_issue_pending(chan);
+ return true;
}
static void rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
{
struct i2c_msg *msg = priv->msg;
+ u32 irqs_to_clear = MDE;
/* FIXME: sometimes, unknown interrupt happened. Do nothing */
- if (!(msr & MDE))
+ if (WARN(!(msr & MDE), "spurious irq"))
+ return;
+
+ if (msr & MAT)
+ irqs_to_clear |= MAT;
+
+ /* Check if DMA can be enabled and take over */
+ if (priv->pos == 1 && rcar_i2c_dma(priv))
return;
if (priv->pos < msg->len) {
@@ -494,13 +575,6 @@ static void rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
*/
rcar_i2c_write(priv, ICRXTX, msg->buf[priv->pos]);
priv->pos++;
-
- /*
- * Try to use DMA to transmit the rest of the data if
- * address transfer phase just finished.
- */
- if (msr & MAT)
- rcar_i2c_dma(priv);
} else {
/*
* The last data was pushed to ICRXTX on _PREV_ empty irq.
@@ -510,31 +584,32 @@ static void rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
* [ICRXTX] -> [SHIFT] -> [I2C bus]
*/
- if (priv->flags & ID_LAST_MSG) {
+ if (priv->flags & ID_LAST_MSG)
/*
* If current msg is the _LAST_ msg,
* prepare stop condition here.
* ID_DONE will be set on STOP irq.
*/
rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
- } else {
+ else
rcar_i2c_next_msg(priv);
- return;
- }
}
- rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_SEND);
+ rcar_i2c_clear_irq(priv, irqs_to_clear);
}
static void rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
{
struct i2c_msg *msg = priv->msg;
+ bool recv_len_init = priv->pos == 0 && msg->flags & I2C_M_RECV_LEN;
+ u32 irqs_to_clear = MDR;
/* FIXME: sometimes, unknown interrupt happened. Do nothing */
if (!(msr & MDR))
return;
if (msr & MAT) {
+ irqs_to_clear |= MAT;
/*
* Address transfer phase finished, but no data at this point.
* Try to use DMA to receive data.
@@ -542,30 +617,48 @@ static void rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
rcar_i2c_dma(priv);
} else if (priv->pos < msg->len) {
/* get received data */
- msg->buf[priv->pos] = rcar_i2c_read(priv, ICRXTX);
+ u8 data = rcar_i2c_read(priv, ICRXTX);
+
+ msg->buf[priv->pos] = data;
+ if (recv_len_init) {
+ if (data == 0 || data > I2C_SMBUS_BLOCK_MAX) {
+ priv->flags |= ID_DONE | ID_EPROTO;
+ return;
+ }
+ msg->len += msg->buf[0];
+ /* Enough data for DMA? */
+ if (rcar_i2c_dma(priv))
+ return;
+ /* new length after RECV_LEN now properly initialized */
+ recv_len_init = false;
+ }
priv->pos++;
}
- /* If next received data is the _LAST_, go to new phase. */
- if (priv->pos + 1 == msg->len) {
+ /*
+ * If next received data is the _LAST_ and we are not waiting for a new
+ * length because of RECV_LEN, then go to a new phase.
+ */
+ if (priv->pos + 1 == msg->len && !recv_len_init) {
if (priv->flags & ID_LAST_MSG) {
rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
} else {
rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);
- priv->flags |= ID_P_REP_AFTER_RD;
+ priv->flags |= ID_REP_AFTER_RD;
}
}
if (priv->pos == msg->len && !(priv->flags & ID_LAST_MSG))
rcar_i2c_next_msg(priv);
- else
- rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_RECV);
+
+ rcar_i2c_clear_irq(priv, irqs_to_clear);
}
static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
{
u32 ssr_raw, ssr_filtered;
u8 value;
+ int ret;
ssr_raw = rcar_i2c_read(priv, ICSSR) & 0xff;
ssr_filtered = ssr_raw & rcar_i2c_read(priv, ICSIER);
@@ -581,29 +674,37 @@ static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
rcar_i2c_write(priv, ICRXTX, value);
rcar_i2c_write(priv, ICSIER, SDE | SSR | SAR);
} else {
- i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+ ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+ if (ret)
+ priv->slave_flags |= ID_SLAVE_NACK;
+
rcar_i2c_read(priv, ICRXTX); /* dummy read */
rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR);
}
- rcar_i2c_write(priv, ICSSR, ~SAR & 0xff);
+ /* Clear SSR, too, because of old STOPs to other clients than us */
+ rcar_i2c_write(priv, ICSSR, ~(SAR | SSR) & 0xff);
}
/* master sent stop */
if (ssr_filtered & SSR) {
i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value);
- rcar_i2c_write(priv, ICSIER, SAR | SSR);
+ rcar_i2c_write(priv, ICSCR, SIE | SDBS); /* clear our NACK */
+ priv->slave_flags &= ~ID_SLAVE_NACK;
+ rcar_i2c_write(priv, ICSIER, SAR);
rcar_i2c_write(priv, ICSSR, ~SSR & 0xff);
}
/* master wants to write to us */
if (ssr_filtered & SDR) {
- int ret;
-
value = rcar_i2c_read(priv, ICRXTX);
ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
- /* Send NACK in case of error */
- rcar_i2c_write(priv, ICSCR, SIE | SDBS | (ret < 0 ? FNA : 0));
+ if (ret)
+ priv->slave_flags |= ID_SLAVE_NACK;
+
+ /* Send NACK in case of error, but it will come 1 byte late :( */
+ rcar_i2c_write(priv, ICSCR, SIE | SDBS |
+ (priv->slave_flags & ID_SLAVE_NACK ? FNA : 0));
rcar_i2c_write(priv, ICSSR, ~SDR & 0xff);
}
@@ -617,21 +718,19 @@ static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
return true;
}
-static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
+/*
+ * This driver has a lock-free design because there are IP cores (at least
+ * R-Car Gen2) which have an inherent race condition in their hardware design.
+ * There, we need to switch to RCAR_BUS_PHASE_DATA as soon as possible after
+ * the interrupt was generated, otherwise an unwanted repeated message gets
+ * generated. It turned out that taking a spinlock at the beginning of the ISR
+ * was already causing repeated messages. Thus, this driver was converted to
+ * the now lockless behaviour. Please keep this in mind when hacking the driver.
+ * R-Car Gen3 seems to have this fixed but earlier versions than R-Car Gen2 are
+ * likely affected. Therefore, we have different interrupt handler entries.
+ */
+static irqreturn_t rcar_i2c_irq(int irq, struct rcar_i2c_priv *priv, u32 msr)
{
- struct rcar_i2c_priv *priv = ptr;
- u32 msr, val;
-
- /* Clear START or STOP immediately, except for REPSTART after read */
- if (likely(!(priv->flags & ID_P_REP_AFTER_RD))) {
- val = rcar_i2c_read(priv, ICMCR);
- rcar_i2c_write(priv, ICMCR, val & RCAR_BUS_MASK_DATA);
- }
-
- msr = rcar_i2c_read(priv, ICMSR);
-
- /* Only handle interrupts that are currently enabled */
- msr &= rcar_i2c_read(priv, ICMIER);
if (!msr) {
if (rcar_i2c_slave_irq(priv))
return IRQ_HANDLED;
@@ -648,7 +747,8 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
/* Nack */
if (msr & MNR) {
/* HW automatically sends STOP after received NACK */
- rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP);
+ if (priv->flags & ID_P_NOT_ATOMIC)
+ rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP);
priv->flags |= ID_NACK;
goto out;
}
@@ -669,12 +769,50 @@ out:
if (priv->flags & ID_DONE) {
rcar_i2c_write(priv, ICMIER, 0);
rcar_i2c_write(priv, ICMSR, 0);
- wake_up(&priv->wait);
+ if (priv->flags & ID_P_NOT_ATOMIC)
+ wake_up(&priv->wait);
}
return IRQ_HANDLED;
}
+static irqreturn_t rcar_i2c_gen2_irq(int irq, void *ptr)
+{
+ struct rcar_i2c_priv *priv = ptr;
+ u32 msr;
+
+ /* Clear START or STOP immediately, except for REPSTART after read */
+ if (likely(!(priv->flags & ID_REP_AFTER_RD)))
+ rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
+
+ /* Only handle interrupts that are currently enabled */
+ msr = rcar_i2c_read(priv, ICMSR);
+ if (priv->flags & ID_P_NOT_ATOMIC)
+ msr &= rcar_i2c_read(priv, ICMIER);
+
+ return rcar_i2c_irq(irq, priv, msr);
+}
+
+static irqreturn_t rcar_i2c_gen3_irq(int irq, void *ptr)
+{
+ struct rcar_i2c_priv *priv = ptr;
+ u32 msr;
+
+ /* Only handle interrupts that are currently enabled */
+ msr = rcar_i2c_read(priv, ICMSR);
+ if (priv->flags & ID_P_NOT_ATOMIC)
+ msr &= rcar_i2c_read(priv, ICMIER);
+
+ /*
+ * Clear START or STOP immediately, except for REPSTART after read or
+ * if a spurious interrupt was detected.
+ */
+ if (likely(!(priv->flags & ID_REP_AFTER_RD) && msr))
+ rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
+
+ return rcar_i2c_irq(irq, priv, msr);
+}
+
static struct dma_chan *rcar_i2c_request_dma_chan(struct device *dev,
enum dma_transfer_direction dir,
dma_addr_t port_addr)
@@ -752,20 +890,18 @@ static void rcar_i2c_release_dma(struct rcar_i2c_priv *priv)
/* I2C is a special case, we need to poll the status of a reset */
static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv)
{
- int i, ret;
+ int ret;
+
+ /* Don't reset if a slave instance is currently running */
+ if (priv->slave)
+ return -EISCONN;
ret = reset_control_reset(priv->rstc);
if (ret)
return ret;
- for (i = 0; i < LOOP_TIMEOUT; i++) {
- ret = reset_control_status(priv->rstc);
- if (ret == 0)
- return 0;
- udelay(1);
- }
-
- return -ETIMEDOUT;
+ return read_poll_timeout_atomic(reset_control_status, ret, ret == 0, 1,
+ 100, false, priv->rstc);
}
static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
@@ -777,6 +913,8 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
int i, ret;
long time_left;
+ priv->flags |= ID_P_NOT_ATOMIC;
+
pm_runtime_get_sync(dev);
/* Check bus state before init otherwise bus busy info will be lost */
@@ -784,14 +922,12 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
if (ret < 0)
goto out;
- /* Gen3 needs a reset before allowing RXDMA once */
- if (priv->devtype == I2C_RCAR_GEN3) {
- priv->flags |= ID_P_NO_RXDMA;
- if (!IS_ERR(priv->rstc)) {
- ret = rcar_i2c_do_reset(priv);
- if (ret == 0)
- priv->flags &= ~ID_P_NO_RXDMA;
- }
+ /* Gen3+ needs a reset. That also allows RXDMA once */
+ if (priv->devtype >= I2C_RCAR_GEN3) {
+ ret = rcar_i2c_do_reset(priv);
+ if (ret)
+ goto out;
+ priv->flags &= ~ID_P_NO_RXDMA;
}
rcar_i2c_init(priv);
@@ -799,18 +935,14 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
for (i = 0; i < num; i++)
rcar_i2c_request_dma(priv, msgs + i);
- /* init first message */
- priv->msg = msgs;
- priv->msgs_left = num;
- priv->flags = (priv->flags & ID_P_MASK) | ID_FIRST_MSG;
- rcar_i2c_prepare_msg(priv);
+ rcar_i2c_first_msg(priv, msgs, num);
time_left = wait_event_timeout(priv->wait, priv->flags & ID_DONE,
num * adap->timeout);
/* cleanup DMA if it couldn't complete properly due to an error */
if (priv->dma_direction != DMA_NONE)
- rcar_i2c_cleanup_dma(priv);
+ rcar_i2c_cleanup_dma(priv, true);
if (!time_left) {
rcar_i2c_init(priv);
@@ -819,6 +951,67 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
ret = -ENXIO;
} else if (priv->flags & ID_ARBLOST) {
ret = -EAGAIN;
+ } else if (priv->flags & ID_EPROTO) {
+ ret = -EPROTO;
+ } else {
+ ret = num - priv->msgs_left; /* The number of transfer */
+ }
+out:
+ pm_runtime_put(dev);
+
+ if (ret < 0 && ret != -ENXIO)
+ dev_err(dev, "error %d : %x\n", ret, priv->flags);
+
+ return ret;
+}
+
+static int rcar_i2c_master_xfer_atomic(struct i2c_adapter *adap,
+ struct i2c_msg *msgs,
+ int num)
+{
+ struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
+ struct device *dev = rcar_i2c_priv_to_dev(priv);
+ unsigned long j;
+ bool time_left;
+ int ret;
+
+ priv->flags &= ~ID_P_NOT_ATOMIC;
+
+ pm_runtime_get_sync(dev);
+
+ /* Check bus state before init otherwise bus busy info will be lost */
+ ret = rcar_i2c_bus_barrier(priv);
+ if (ret < 0)
+ goto out;
+
+ rcar_i2c_init(priv);
+ rcar_i2c_first_msg(priv, msgs, num);
+
+ j = jiffies + num * adap->timeout;
+ do {
+ u32 msr = rcar_i2c_read(priv, ICMSR);
+
+ msr &= (rcar_i2c_is_recv(priv) ? RCAR_IRQ_RECV : RCAR_IRQ_SEND) | RCAR_IRQ_STOP;
+
+ if (msr) {
+ if (priv->devtype < I2C_RCAR_GEN3)
+ rcar_i2c_gen2_irq(0, priv);
+ else
+ rcar_i2c_gen3_irq(0, priv);
+ }
+
+ time_left = time_before_eq(jiffies, j);
+ } while (!(priv->flags & ID_DONE) && time_left);
+
+ if (!time_left) {
+ rcar_i2c_init(priv);
+ ret = -ETIMEDOUT;
+ } else if (priv->flags & ID_NACK) {
+ ret = -ENXIO;
+ } else if (priv->flags & ID_ARBLOST) {
+ ret = -EAGAIN;
+ } else if (priv->flags & ID_EPROTO) {
+ ret = -EPROTO;
} else {
ret = num - priv->msgs_left; /* The number of transfer */
}
@@ -847,7 +1040,7 @@ static int rcar_reg_slave(struct i2c_client *slave)
priv->slave = slave;
rcar_i2c_write(priv, ICSAR, slave->addr);
rcar_i2c_write(priv, ICSSR, 0);
- rcar_i2c_write(priv, ICSIER, SAR | SSR);
+ rcar_i2c_write(priv, ICSIER, SAR);
rcar_i2c_write(priv, ICSCR, SIE | SDBS);
return 0;
@@ -859,8 +1052,10 @@ static int rcar_unreg_slave(struct i2c_client *slave)
WARN_ON(!priv->slave);
- rcar_i2c_write(priv, ICSIER, 0);
- rcar_i2c_write(priv, ICSCR, 0);
+ /* ensure no irq is running before clearing ptr */
+ disable_irq(priv->irq);
+ rcar_i2c_reset_slave(priv);
+ enable_irq(priv->irq);
priv->slave = NULL;
@@ -871,21 +1066,29 @@ static int rcar_unreg_slave(struct i2c_client *slave)
static u32 rcar_i2c_func(struct i2c_adapter *adap)
{
+ struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
+
/*
* This HW can't do:
* I2C_SMBUS_QUICK (setting FSB during START didn't work)
* I2C_M_NOSTART (automatically sends address after START)
* I2C_M_IGNORE_NAK (automatically sends STOP after NAK)
*/
- return I2C_FUNC_I2C | I2C_FUNC_SLAVE |
- (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+ u32 func = I2C_FUNC_I2C | I2C_FUNC_SLAVE |
+ (I2C_FUNC_SMBUS_EMUL_ALL & ~I2C_FUNC_SMBUS_QUICK);
+
+ if (priv->flags & ID_P_HOST_NOTIFY)
+ func |= I2C_FUNC_SMBUS_HOST_NOTIFY;
+
+ return func;
}
static const struct i2c_algorithm rcar_i2c_algo = {
- .master_xfer = rcar_i2c_master_xfer,
- .functionality = rcar_i2c_func,
- .reg_slave = rcar_reg_slave,
- .unreg_slave = rcar_unreg_slave,
+ .xfer = rcar_i2c_master_xfer,
+ .xfer_atomic = rcar_i2c_master_xfer_atomic,
+ .functionality = rcar_i2c_func,
+ .reg_slave = rcar_reg_slave,
+ .unreg_slave = rcar_unreg_slave,
};
static const struct i2c_adapter_quirks rcar_i2c_quirks = {
@@ -902,10 +1105,12 @@ static const struct of_device_id rcar_i2c_dt_ids[] = {
{ .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 },
{ .compatible = "renesas,i2c-r8a7795", .data = (void *)I2C_RCAR_GEN3 },
{ .compatible = "renesas,i2c-r8a7796", .data = (void *)I2C_RCAR_GEN3 },
- { .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 }, /* Deprecated */
+ /* S4 has no FM+ bit */
+ { .compatible = "renesas,i2c-r8a779f0", .data = (void *)I2C_RCAR_GEN3 },
{ .compatible = "renesas,rcar-gen1-i2c", .data = (void *)I2C_RCAR_GEN1 },
{ .compatible = "renesas,rcar-gen2-i2c", .data = (void *)I2C_RCAR_GEN2 },
{ .compatible = "renesas,rcar-gen3-i2c", .data = (void *)I2C_RCAR_GEN3 },
+ { .compatible = "renesas,rcar-gen4-i2c", .data = (void *)I2C_RCAR_GEN4 },
{},
};
MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
@@ -915,8 +1120,12 @@ static int rcar_i2c_probe(struct platform_device *pdev)
struct rcar_i2c_priv *priv;
struct i2c_adapter *adap;
struct device *dev = &pdev->dev;
- struct i2c_timings i2c_t;
- int irq, ret;
+ unsigned long irqflags = 0;
+ irqreturn_t (*irqhandler)(int irq, void *ptr) = rcar_i2c_gen3_irq;
+ int ret;
+
+ /* Otherwise logic will break because some bytes must always use PIO */
+ BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length");
priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL);
if (!priv)
@@ -928,9 +1137,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
return PTR_ERR(priv->clk);
}
- priv->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-
- priv->io = devm_ioremap_resource(dev, priv->res);
+ priv->io = devm_platform_get_and_ioremap_resource(pdev, 0, &priv->res);
if (IS_ERR(priv->io))
return PTR_ERR(priv->io);
@@ -947,9 +1154,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
adap->bus_recovery_info = &rcar_i2c_bri;
adap->quirks = &rcar_i2c_quirks;
i2c_set_adapdata(adap, priv);
- strlcpy(adap->name, pdev->name, sizeof(adap->name));
-
- i2c_parse_fw_timings(dev, &i2c_t, false);
+ strscpy(adap->name, pdev->name, sizeof(adap->name));
/* Init DMA */
sg_init_table(&priv->sg, 1);
@@ -959,68 +1164,121 @@ static int rcar_i2c_probe(struct platform_device *pdev)
/* Activate device for clock calculation */
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
- ret = rcar_i2c_clock_calculate(priv, &i2c_t);
- if (ret < 0)
- goto out_pm_put;
-
- if (priv->devtype == I2C_RCAR_GEN3) {
- priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
- if (!IS_ERR(priv->rstc)) {
- ret = reset_control_status(priv->rstc);
- if (ret < 0)
- priv->rstc = ERR_PTR(-ENOTSUPP);
- }
+ ret = rcar_i2c_clock_calculate(priv);
+ if (ret < 0) {
+ pm_runtime_put(dev);
+ goto out_pm_disable;
}
+ /* Bring hardware to known state */
+ rcar_i2c_init(priv);
+ rcar_i2c_reset_slave(priv);
+
/* Stay always active when multi-master to keep arbitration working */
if (of_property_read_bool(dev->of_node, "multi-master"))
priv->flags |= ID_P_PM_BLOCKED;
else
pm_runtime_put(dev);
+ if (of_property_read_bool(dev->of_node, "smbus"))
+ priv->flags |= ID_P_HOST_NOTIFY;
+
+ if (priv->devtype < I2C_RCAR_GEN3) {
+ irqflags |= IRQF_NO_THREAD;
+ irqhandler = rcar_i2c_gen2_irq;
+ } else {
+ /* R-Car Gen3+ needs a reset before every transfer */
+ priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(priv->rstc)) {
+ ret = PTR_ERR(priv->rstc);
+ goto out_pm_put;
+ }
+
+ ret = reset_control_status(priv->rstc);
+ if (ret < 0)
+ goto out_pm_put;
+
+ /* hard reset disturbs HostNotify local target, so disable it */
+ priv->flags &= ~ID_P_HOST_NOTIFY;
+ }
- irq = platform_get_irq(pdev, 0);
- ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0, dev_name(dev), priv);
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ goto out_pm_put;
+ priv->irq = ret;
+ ret = devm_request_irq(dev, priv->irq, irqhandler, irqflags, dev_name(dev), priv);
if (ret < 0) {
- dev_err(dev, "cannot get irq %d\n", irq);
- goto out_pm_disable;
+ dev_err(dev, "cannot get irq %d\n", priv->irq);
+ goto out_pm_put;
}
platform_set_drvdata(pdev, priv);
ret = i2c_add_numbered_adapter(adap);
if (ret < 0)
- goto out_pm_disable;
+ goto out_pm_put;
+
+ if (priv->flags & ID_P_HOST_NOTIFY) {
+ priv->host_notify_client = i2c_new_slave_host_notify_device(adap);
+ if (IS_ERR(priv->host_notify_client)) {
+ ret = PTR_ERR(priv->host_notify_client);
+ goto out_del_device;
+ }
+ }
dev_info(dev, "probed\n");
return 0;
+ out_del_device:
+ i2c_del_adapter(&priv->adap);
out_pm_put:
- pm_runtime_put(dev);
+ if (priv->flags & ID_P_PM_BLOCKED)
+ pm_runtime_put(dev);
out_pm_disable:
pm_runtime_disable(dev);
return ret;
}
-static int rcar_i2c_remove(struct platform_device *pdev)
+static void rcar_i2c_remove(struct platform_device *pdev)
{
struct rcar_i2c_priv *priv = platform_get_drvdata(pdev);
struct device *dev = &pdev->dev;
+ if (priv->host_notify_client)
+ i2c_free_slave_host_notify_device(priv->host_notify_client);
i2c_del_adapter(&priv->adap);
rcar_i2c_release_dma(priv);
if (priv->flags & ID_P_PM_BLOCKED)
pm_runtime_put(dev);
pm_runtime_disable(dev);
+}
+
+static int rcar_i2c_suspend(struct device *dev)
+{
+ struct rcar_i2c_priv *priv = dev_get_drvdata(dev);
+
+ i2c_mark_adapter_suspended(&priv->adap);
+ return 0;
+}
+static int rcar_i2c_resume(struct device *dev)
+{
+ struct rcar_i2c_priv *priv = dev_get_drvdata(dev);
+
+ i2c_mark_adapter_resumed(&priv->adap);
return 0;
}
+static const struct dev_pm_ops rcar_i2c_pm_ops = {
+ NOIRQ_SYSTEM_SLEEP_PM_OPS(rcar_i2c_suspend, rcar_i2c_resume)
+};
+
static struct platform_driver rcar_i2c_driver = {
.driver = {
.name = "i2c-rcar",
.of_match_table = rcar_i2c_dt_ids,
+ .pm = pm_sleep_ptr(&rcar_i2c_pm_ops),
},
.probe = rcar_i2c_probe,
.remove = rcar_i2c_remove,