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Diffstat (limited to 'drivers/i2c/busses/i2c-omap.c')
-rw-r--r--drivers/i2c/busses/i2c-omap.c226
1 files changed, 146 insertions, 80 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index b1086bfb0465..d9f590f0c384 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* TI OMAP I2C master mode driver
*
@@ -12,16 +13,6 @@
* Juha Yrjölä <juha.yrjola@solidboot.com>
* Syed Khasim <x0khasim@ti.com>
* Nishant Menon <nm@ti.com>
- *
- * 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.
*/
#include <linux/module.h>
@@ -33,12 +24,13 @@
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/mux/consumer.h>
#include <linux/of.h>
-#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/platform_data/i2c-omap.h>
#include <linux/pm_runtime.h>
#include <linux/pinctrl/consumer.h>
+#include <linux/property.h>
/* I2C controller revisions */
#define OMAP_I2C_OMAP1_REV_2 0x20
@@ -220,6 +212,7 @@ struct omap_i2c_dev {
u16 syscstate;
u16 westate;
u16 errata;
+ struct mux_state *mux_state;
};
static const u8 reg_map_ip_v1[] = {
@@ -269,6 +262,8 @@ static const u8 reg_map_ip_v2[] = {
[OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
};
+static int omap_i2c_xfer_data(struct omap_i2c_dev *omap);
+
static inline void omap_i2c_write_reg(struct omap_i2c_dev *omap,
int reg, u16 val)
{
@@ -648,15 +643,28 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *omap, u8 size, bool is_rx)
(1000 * omap->speed / 8);
}
+static void omap_i2c_wait(struct omap_i2c_dev *omap)
+{
+ u16 stat;
+ u16 mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
+ int count = 0;
+
+ do {
+ stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
+ count++;
+ } while (!(stat & mask) && count < 5);
+}
+
/*
* Low level master read/write transaction.
*/
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
- struct i2c_msg *msg, int stop)
+ struct i2c_msg *msg, int stop, bool polling)
{
struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
- unsigned long timeout;
+ unsigned long time_left;
u16 w;
+ int ret;
dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
@@ -680,7 +688,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, w);
- reinit_completion(&omap->cmd_complete);
+ if (!polling)
+ reinit_completion(&omap->cmd_complete);
omap->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
@@ -732,10 +741,19 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
* REVISIT: We should abort the transfer on signals, but the bus goes
* into arbitration and we're currently unable to recover from it.
*/
- timeout = wait_for_completion_timeout(&omap->cmd_complete,
- OMAP_I2C_TIMEOUT);
- if (timeout == 0) {
- dev_err(omap->dev, "controller timed out\n");
+ if (!polling) {
+ time_left = wait_for_completion_timeout(&omap->cmd_complete,
+ OMAP_I2C_TIMEOUT);
+ } else {
+ do {
+ omap_i2c_wait(omap);
+ ret = omap_i2c_xfer_data(omap);
+ } while (ret == -EAGAIN);
+
+ time_left = !ret;
+ }
+
+ if (time_left == 0) {
omap_i2c_reset(omap);
__omap_i2c_init(omap);
return -ETIMEDOUT;
@@ -772,7 +790,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
* to do the work during IRQ processing.
*/
static int
-omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+omap_i2c_xfer_common(struct i2c_adapter *adap, struct i2c_msg msgs[], int num,
+ bool polling)
{
struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
int i;
@@ -794,7 +813,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
omap->set_mpu_wkup_lat(omap->dev, omap->latency);
for (i = 0; i < num; i++) {
- r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
+ r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)),
+ polling);
if (r != 0)
break;
}
@@ -808,11 +828,22 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
omap->set_mpu_wkup_lat(omap->dev, -1);
out:
- pm_runtime_mark_last_busy(omap->dev);
pm_runtime_put_autosuspend(omap->dev);
return r;
}
+static int
+omap_i2c_xfer_irq(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+{
+ return omap_i2c_xfer_common(adap, msgs, num, false);
+}
+
+static int
+omap_i2c_xfer_polling(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+{
+ return omap_i2c_xfer_common(adap, msgs, num, true);
+}
+
static u32
omap_i2c_func(struct i2c_adapter *adap)
{
@@ -1018,27 +1049,8 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *omap, u8 num_bytes,
return 0;
}
-static irqreturn_t
-omap_i2c_isr(int irq, void *dev_id)
+static int omap_i2c_xfer_data(struct omap_i2c_dev *omap)
{
- struct omap_i2c_dev *omap = dev_id;
- irqreturn_t ret = IRQ_HANDLED;
- u16 mask;
- u16 stat;
-
- stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
- mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
-
- if (stat & mask)
- ret = IRQ_WAKE_THREAD;
-
- return ret;
-}
-
-static irqreturn_t
-omap_i2c_isr_thread(int this_irq, void *dev_id)
-{
- struct omap_i2c_dev *omap = dev_id;
u16 bits;
u16 stat;
int err = 0, count = 0;
@@ -1056,7 +1068,8 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
if (!stat) {
/* my work here is done */
- goto out;
+ err = -EAGAIN;
+ break;
}
dev_dbg(omap->dev, "IRQ (ISR = 0x%04x)\n", stat);
@@ -1066,8 +1079,13 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
}
if (stat & OMAP_I2C_STAT_NACK) {
- err |= OMAP_I2C_STAT_NACK;
+ omap->cmd_err |= OMAP_I2C_STAT_NACK;
omap_i2c_ack_stat(omap, OMAP_I2C_STAT_NACK);
+
+ if (!(stat & ~OMAP_I2C_STAT_NACK)) {
+ err = -EAGAIN;
+ break;
+ }
}
if (stat & OMAP_I2C_STAT_AL) {
@@ -1165,15 +1183,26 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
}
} while (stat);
- omap_i2c_complete_cmd(omap, err);
+ return err;
+}
+
+static irqreturn_t
+omap_i2c_isr_thread(int this_irq, void *dev_id)
+{
+ int ret;
+ struct omap_i2c_dev *omap = dev_id;
+
+ ret = omap_i2c_xfer_data(omap);
+ if (ret != -EAGAIN)
+ omap_i2c_complete_cmd(omap, ret);
-out:
return IRQ_HANDLED;
}
static const struct i2c_algorithm omap_i2c_algo = {
- .master_xfer = omap_i2c_xfer,
- .functionality = omap_i2c_func,
+ .xfer = omap_i2c_xfer_irq,
+ .xfer_atomic = omap_i2c_xfer_polling,
+ .functionality = omap_i2c_func,
};
static const struct i2c_adapter_quirks omap_i2c_quirks = {
@@ -1221,7 +1250,7 @@ static const struct of_device_id omap_i2c_of_match[] = {
.compatible = "ti,omap2420-i2c",
.data = &omap2420_pdata,
},
- { },
+ { }
};
MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
#endif
@@ -1314,36 +1343,30 @@ omap_i2c_probe(struct platform_device *pdev)
{
struct omap_i2c_dev *omap;
struct i2c_adapter *adap;
- struct resource *mem;
const struct omap_i2c_bus_platform_data *pdata =
dev_get_platdata(&pdev->dev);
struct device_node *node = pdev->dev.of_node;
- const struct of_device_id *match;
int irq;
int r;
u32 rev;
u16 minor, major;
irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(&pdev->dev, "no irq resource?\n");
+ if (irq < 0)
return irq;
- }
omap = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
if (!omap)
return -ENOMEM;
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- omap->base = devm_ioremap_resource(&pdev->dev, mem);
+ omap->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(omap->base))
return PTR_ERR(omap->base);
- match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
- if (match) {
- u32 freq = 100000; /* default to 100000 Hz */
+ if (pdev->dev.of_node) {
+ u32 freq = I2C_MAX_STANDARD_MODE_FREQ;
- pdata = match->data;
+ pdata = device_get_match_data(&pdev->dev);
omap->flags = pdata->flags;
of_property_read_u32(node, "clock-frequency", &freq);
@@ -1367,9 +1390,9 @@ omap_i2c_probe(struct platform_device *pdev)
pm_runtime_set_autosuspend_delay(omap->dev, OMAP_I2C_PM_TIMEOUT);
pm_runtime_use_autosuspend(omap->dev);
- r = pm_runtime_get_sync(omap->dev);
+ r = pm_runtime_resume_and_get(omap->dev);
if (r < 0)
- goto err_free_mem;
+ goto err_disable_pm;
/*
* Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2.
@@ -1388,7 +1411,6 @@ omap_i2c_probe(struct platform_device *pdev)
major = OMAP_I2C_REV_SCHEME_0_MAJOR(omap->rev);
break;
case OMAP_I2C_SCHEME_1:
- /* FALLTHROUGH */
default:
omap->regs = (u8 *)reg_map_ip_v2;
rev = (rev << 16) |
@@ -1431,15 +1453,34 @@ omap_i2c_probe(struct platform_device *pdev)
(1000 * omap->speed / 8);
}
+ if (of_property_present(node, "mux-states")) {
+ struct mux_state *mux_state;
+
+ mux_state = devm_mux_state_get(&pdev->dev, NULL);
+ if (IS_ERR(mux_state)) {
+ r = PTR_ERR(mux_state);
+ dev_dbg(&pdev->dev, "failed to get I2C mux: %d\n", r);
+ goto err_put_pm;
+ }
+ omap->mux_state = mux_state;
+ r = mux_state_select(omap->mux_state);
+ if (r) {
+ dev_err(&pdev->dev, "failed to select I2C mux: %d\n", r);
+ goto err_put_pm;
+ }
+ }
+
/* reset ASAP, clearing any IRQs */
- omap_i2c_init(omap);
+ r = omap_i2c_init(omap);
+ if (r)
+ goto err_mux_state_deselect;
if (omap->rev < OMAP_I2C_OMAP1_REV_2)
r = devm_request_irq(&pdev->dev, omap->irq, omap_i2c_omap1_isr,
IRQF_NO_SUSPEND, pdev->name, omap);
else
r = devm_request_threaded_irq(&pdev->dev, omap->irq,
- omap_i2c_isr, omap_i2c_isr_thread,
+ NULL, omap_i2c_isr_thread,
IRQF_NO_SUSPEND | IRQF_ONESHOT,
pdev->name, omap);
@@ -1452,7 +1493,7 @@ omap_i2c_probe(struct platform_device *pdev)
i2c_set_adapdata(adap, omap);
adap->owner = THIS_MODULE;
adap->class = I2C_CLASS_DEPRECATED;
- strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
+ strscpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
adap->algo = &omap_i2c_algo;
adap->quirks = &omap_i2c_quirks;
adap->dev.parent = &pdev->dev;
@@ -1468,39 +1509,45 @@ omap_i2c_probe(struct platform_device *pdev)
dev_info(omap->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
major, minor, omap->speed);
- pm_runtime_mark_last_busy(omap->dev);
pm_runtime_put_autosuspend(omap->dev);
return 0;
err_unuse_clocks:
omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
- pm_runtime_dont_use_autosuspend(omap->dev);
+err_mux_state_deselect:
+ if (omap->mux_state)
+ mux_state_deselect(omap->mux_state);
+err_put_pm:
pm_runtime_put_sync(omap->dev);
+err_disable_pm:
+ pm_runtime_dont_use_autosuspend(omap->dev);
pm_runtime_disable(&pdev->dev);
-err_free_mem:
return r;
}
-static int omap_i2c_remove(struct platform_device *pdev)
+static void omap_i2c_remove(struct platform_device *pdev)
{
struct omap_i2c_dev *omap = platform_get_drvdata(pdev);
int ret;
i2c_del_adapter(&omap->adapter);
+
+ if (omap->mux_state)
+ mux_state_deselect(omap->mux_state);
+
ret = pm_runtime_get_sync(&pdev->dev);
if (ret < 0)
- return ret;
+ dev_err(omap->dev, "Failed to resume hardware, skip disable\n");
+ else
+ omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
- omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- return 0;
}
-#ifdef CONFIG_PM
static int omap_i2c_runtime_suspend(struct device *dev)
{
struct omap_i2c_dev *omap = dev_get_drvdata(dev);
@@ -1541,21 +1588,40 @@ static int omap_i2c_runtime_resume(struct device *dev)
return 0;
}
+static int omap_i2c_suspend(struct device *dev)
+{
+ /*
+ * If the controller is autosuspended, there is no way to wakeup it once
+ * runtime pm is disabled (in suspend_late()).
+ * But a device may need the controller up during suspend_noirq() or
+ * resume_noirq().
+ * Wakeup the controller while runtime pm is enabled, so it is available
+ * until its suspend_noirq(), and from resume_noirq().
+ */
+ return pm_runtime_resume_and_get(dev);
+}
+
+static int omap_i2c_resume(struct device *dev)
+{
+ pm_runtime_put_autosuspend(dev);
+
+ return 0;
+}
+
static const struct dev_pm_ops omap_i2c_pm_ops = {
- SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
- omap_i2c_runtime_resume, NULL)
+ NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, omap_i2c_resume)
+ RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
+ omap_i2c_runtime_resume, NULL)
};
-#define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
-#else
-#define OMAP_I2C_PM_OPS NULL
-#endif /* CONFIG_PM */
static struct platform_driver omap_i2c_driver = {
.probe = omap_i2c_probe,
.remove = omap_i2c_remove,
.driver = {
.name = "omap_i2c",
- .pm = OMAP_I2C_PM_OPS,
+ .pm = pm_ptr(&omap_i2c_pm_ops),
.of_match_table = of_match_ptr(omap_i2c_of_match),
},
};