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authorMark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>2020-08-27 10:35:16 +1200
committerWolfram Sang <wsa@kernel.org>2020-12-02 21:29:30 +0100
commit9c7cae2427715502227f823364a6a77828fdf3ea (patch)
tree9b48fab235b6c6792f50ae4ce207dfa9f99d92fb /drivers/i2c
parent5df324b5f4baa3a51990f078fa445800197dfba3 (diff)
i2c: mv64xxx: Add bus error recovery
This adds i2c bus recovery to the mv64xxx driver. Implement bus recovery to recover from SCL/SDA stuck low. This uses the generic recovery function, setting the clock/data lines as GPIO pins, and sending 9 clocks to try and recover the bus. Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz> [wsa: added some curly braces] Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-mv64xxx.c29
1 files changed, 28 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index e0e45fc19b8f..5cfe70aedced 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -17,6 +17,7 @@
#include <linux/interrupt.h>
#include <linux/mv643xx_i2c.h>
#include <linux/platform_device.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/reset.h>
#include <linux/io.h>
#include <linux/of.h>
@@ -147,6 +148,7 @@ struct mv64xxx_i2c_data {
bool irq_clear_inverted;
/* Clk div is 2 to the power n, not 2 to the power n + 1 */
bool clk_n_base_0;
+ struct i2c_bus_recovery_info rinfo;
};
static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = {
@@ -325,7 +327,8 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
drv_data->msg->flags);
drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
mv64xxx_i2c_hw_init(drv_data);
- drv_data->rc = -EIO;
+ i2c_recover_bus(&drv_data->adapter);
+ drv_data->rc = -EAGAIN;
}
}
@@ -561,6 +564,7 @@ mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
"time_left: %d\n", drv_data->block,
(int)time_left);
mv64xxx_i2c_hw_init(drv_data);
+ i2c_recover_bus(&drv_data->adapter);
}
} else
spin_unlock_irqrestore(&drv_data->lock, flags);
@@ -870,6 +874,25 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
}
#endif /* CONFIG_OF */
+static int mv64xxx_i2c_init_recovery_info(struct mv64xxx_i2c_data *drv_data,
+ struct device *dev)
+{
+ struct i2c_bus_recovery_info *rinfo = &drv_data->rinfo;
+
+ rinfo->pinctrl = devm_pinctrl_get(dev);
+ if (IS_ERR(rinfo->pinctrl)) {
+ if (PTR_ERR(rinfo->pinctrl) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ dev_info(dev, "can't get pinctrl, bus recovery not supported\n");
+ return PTR_ERR(rinfo->pinctrl);
+ } else if (!rinfo->pinctrl) {
+ return -ENODEV;
+ }
+
+ drv_data->adapter.bus_recovery_info = rinfo;
+ return 0;
+}
+
static int
mv64xxx_i2c_probe(struct platform_device *pd)
{
@@ -926,6 +949,10 @@ mv64xxx_i2c_probe(struct platform_device *pd)
goto exit_reset;
}
+ rc = mv64xxx_i2c_init_recovery_info(drv_data, &pd->dev);
+ if (rc == -EPROBE_DEFER)
+ goto exit_reset;
+
drv_data->adapter.dev.parent = &pd->dev;
drv_data->adapter.algo = &mv64xxx_i2c_algo;
drv_data->adapter.owner = THIS_MODULE;