diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-cadence.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c index 8f61a633c42c..f1a67c410ad3 100644 --- a/drivers/i2c/busses/i2c-cadence.c +++ b/drivers/i2c/busses/i2c-cadence.c @@ -16,6 +16,7 @@ #include <linux/of.h> #include <linux/pm_runtime.h> #include <linux/pinctrl/consumer.h> +#include <linux/reset.h> /* Register offsets for the I2C device. */ #define CDNS_I2C_CR_OFFSET 0x00 /* Control Register, RW */ @@ -178,6 +179,7 @@ enum cdns_i2c_slave_state { * @bus_hold_flag: Flag used in repeated start for clearing HOLD bit * @clk: Pointer to struct clk * @clk_rate_change_nb: Notifier block for clock rate changes + * @reset: Reset control for the device * @quirks: flag for broken hold bit usage in r1p10 * @ctrl_reg: Cached value of the control register. * @ctrl_reg_diva_divb: value of fields DIV_A and DIV_B from CR register @@ -204,6 +206,7 @@ struct cdns_i2c { unsigned int bus_hold_flag; struct clk *clk; struct notifier_block clk_rate_change_nb; + struct reset_control *reset; u32 quirks; u32 ctrl_reg; struct i2c_bus_recovery_info rinfo; @@ -1325,10 +1328,22 @@ static int cdns_i2c_probe(struct platform_device *pdev) return dev_err_probe(&pdev->dev, PTR_ERR(id->clk), "input clock not found.\n"); + id->reset = devm_reset_control_get_optional_shared(&pdev->dev, NULL); + if (IS_ERR(id->reset)) + return dev_err_probe(&pdev->dev, PTR_ERR(id->reset), + "Failed to request reset.\n"); + ret = clk_prepare_enable(id->clk); if (ret) dev_err(&pdev->dev, "Unable to enable clock.\n"); + ret = reset_control_deassert(id->reset); + if (ret) { + dev_err_probe(&pdev->dev, ret, + "Failed to de-assert reset.\n"); + goto err_clk_dis; + } + pm_runtime_set_autosuspend_delay(id->dev, CNDS_I2C_PM_TIMEOUT); pm_runtime_use_autosuspend(id->dev); pm_runtime_set_active(id->dev); @@ -1360,28 +1375,30 @@ static int cdns_i2c_probe(struct platform_device *pdev) if (ret) { dev_err(&pdev->dev, "invalid SCL clock: %u Hz\n", id->i2c_clk); ret = -EINVAL; - goto err_clk_dis; + goto err_clk_notifier_unregister; } ret = devm_request_irq(&pdev->dev, irq, cdns_i2c_isr, 0, DRIVER_NAME, id); if (ret) { dev_err(&pdev->dev, "cannot get irq %d\n", irq); - goto err_clk_dis; + goto err_clk_notifier_unregister; } cdns_i2c_init(id); ret = i2c_add_adapter(&id->adap); if (ret < 0) - goto err_clk_dis; + goto err_clk_notifier_unregister; dev_info(&pdev->dev, "%u kHz mmio %08lx irq %d\n", id->i2c_clk / 1000, (unsigned long)r_mem->start, irq); return 0; -err_clk_dis: +err_clk_notifier_unregister: clk_notifier_unregister(id->clk, &id->clk_rate_change_nb); + reset_control_assert(id->reset); +err_clk_dis: clk_disable_unprepare(id->clk); pm_runtime_disable(&pdev->dev); pm_runtime_set_suspended(&pdev->dev); @@ -1406,6 +1423,7 @@ static int cdns_i2c_remove(struct platform_device *pdev) i2c_del_adapter(&id->adap); clk_notifier_unregister(id->clk, &id->clk_rate_change_nb); + reset_control_assert(id->reset); clk_disable_unprepare(id->clk); return 0; |