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 <[email protected]> --- Changes in v2: - use generic GPIO recovery function. Changes in v3: - remove call to i2c_recover_bus() during probe. - change error message to info when pinctrl fails, matching other similar code. - handle a lack of pinctrl information better. drivers/i2c/busses/i2c-mv64xxx.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c index 8d9d4ffdcd24..5c5f1d797986 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; } } @@ -562,6 +565,7 @@ 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); @@ -871,6 +875,24 @@ 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) { @@ -927,6 +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; -- 2.28.0
