diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-cadence.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-cadence.c | 73 |
1 files changed, 46 insertions, 27 deletions
diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c index 84deed6571bd..6b08d1607b7a 100644 --- a/drivers/i2c/busses/i2c-cadence.c +++ b/drivers/i2c/busses/i2c-cadence.c @@ -18,6 +18,7 @@ #include <linux/module.h> #include <linux/platform_device.h> #include <linux/of.h> +#include <linux/pm_runtime.h> /* Register offsets for the I2C device. */ #define CDNS_I2C_CR_OFFSET 0x00 /* Control Register, RW */ @@ -96,6 +97,8 @@ CDNS_I2C_IXR_COMP) #define CDNS_I2C_TIMEOUT msecs_to_jiffies(1000) +/* timeout for pm runtime autosuspend */ +#define CNDS_I2C_PM_TIMEOUT 1000 /* ms */ #define CDNS_I2C_FIFO_DEPTH 16 /* FIFO depth at which the DATA interrupt occurs */ @@ -128,7 +131,6 @@ * @xfer_done: Transfer complete status * @p_send_buf: Pointer to transmit buffer * @p_recv_buf: Pointer to receive buffer - * @suspended: Flag holding the device's PM status * @send_count: Number of bytes still expected to send * @recv_count: Number of bytes still expected to receive * @curr_recv_count: Number of bytes to be received in current transfer @@ -141,6 +143,7 @@ * @quirks: flag for broken hold bit usage in r1p10 */ struct cdns_i2c { + struct device *dev; void __iomem *membase; struct i2c_adapter adap; struct i2c_msg *p_msg; @@ -148,7 +151,6 @@ struct cdns_i2c { struct completion xfer_done; unsigned char *p_send_buf; unsigned char *p_recv_buf; - u8 suspended; unsigned int send_count; unsigned int recv_count; unsigned int curr_recv_count; @@ -569,9 +571,14 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, struct cdns_i2c *id = adap->algo_data; bool hold_quirk; + ret = pm_runtime_get_sync(id->dev); + if (ret < 0) + return ret; /* Check if the bus is free */ - if (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & CDNS_I2C_SR_BA) - return -EAGAIN; + if (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & CDNS_I2C_SR_BA) { + ret = -EAGAIN; + goto out; + } hold_quirk = !!(id->quirks & CDNS_I2C_BROKEN_HOLD_BIT); /* @@ -590,7 +597,8 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, if (msgs[count].flags & I2C_M_RD) { dev_warn(adap->dev.parent, "Can't do repeated start after a receive message\n"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } } id->bus_hold_flag = 1; @@ -608,20 +616,26 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, ret = cdns_i2c_process_msg(id, msgs, adap); if (ret) - return ret; + goto out; /* Report the other error interrupts to application */ if (id->err_status) { cdns_i2c_master_reset(adap); - if (id->err_status & CDNS_I2C_IXR_NACK) - return -ENXIO; - - return -EIO; + if (id->err_status & CDNS_I2C_IXR_NACK) { + ret = -ENXIO; + goto out; + } + ret = -EIO; + goto out; } } - return num; + ret = num; +out: + pm_runtime_mark_last_busy(id->dev); + pm_runtime_put_autosuspend(id->dev); + return ret; } /** @@ -760,7 +774,7 @@ static int cdns_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long struct clk_notifier_data *ndata = data; struct cdns_i2c *id = to_cdns_i2c(nb); - if (id->suspended) + if (pm_runtime_suspended(id->dev)) return NOTIFY_OK; switch (event) { @@ -808,14 +822,12 @@ static int cdns_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long * * Return: 0 always */ -static int __maybe_unused cdns_i2c_suspend(struct device *_dev) +static int __maybe_unused cdns_i2c_runtime_suspend(struct device *dev) { - struct platform_device *pdev = container_of(_dev, - struct platform_device, dev); + struct platform_device *pdev = to_platform_device(dev); struct cdns_i2c *xi2c = platform_get_drvdata(pdev); clk_disable(xi2c->clk); - xi2c->suspended = 1; return 0; } @@ -828,26 +840,25 @@ static int __maybe_unused cdns_i2c_suspend(struct device *_dev) * * Return: 0 on success and error value on error */ -static int __maybe_unused cdns_i2c_resume(struct device *_dev) +static int __maybe_unused cdns_i2c_runtime_resume(struct device *dev) { - struct platform_device *pdev = container_of(_dev, - struct platform_device, dev); + struct platform_device *pdev = to_platform_device(dev); struct cdns_i2c *xi2c = platform_get_drvdata(pdev); int ret; ret = clk_enable(xi2c->clk); if (ret) { - dev_err(_dev, "Cannot enable clock.\n"); + dev_err(dev, "Cannot enable clock.\n"); return ret; } - xi2c->suspended = 0; - return 0; } -static SIMPLE_DEV_PM_OPS(cdns_i2c_dev_pm_ops, cdns_i2c_suspend, - cdns_i2c_resume); +static const struct dev_pm_ops cdns_i2c_dev_pm_ops = { + SET_RUNTIME_PM_OPS(cdns_i2c_runtime_suspend, + cdns_i2c_runtime_resume, NULL) +}; static const struct cdns_platform_data r1p10_i2c_def = { .quirks = CDNS_I2C_BROKEN_HOLD_BIT, @@ -881,6 +892,7 @@ static int cdns_i2c_probe(struct platform_device *pdev) if (!id) return -ENOMEM; + id->dev = &pdev->dev; platform_set_drvdata(pdev, id); match = of_match_node(cdns_i2c_of_match, pdev->dev.of_node); @@ -913,10 +925,14 @@ static int cdns_i2c_probe(struct platform_device *pdev) return PTR_ERR(id->clk); } ret = clk_prepare_enable(id->clk); - if (ret) { + if (ret) dev_err(&pdev->dev, "Unable to enable clock.\n"); - return ret; - } + + pm_runtime_enable(id->dev); + pm_runtime_set_autosuspend_delay(id->dev, CNDS_I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(id->dev); + pm_runtime_set_active(id->dev); + id->clk_rate_change_nb.notifier_call = cdns_i2c_clk_notifier_cb; if (clk_notifier_register(id->clk, &id->clk_rate_change_nb)) dev_warn(&pdev->dev, "Unable to register clock notifier.\n"); @@ -966,6 +982,8 @@ static int cdns_i2c_probe(struct platform_device *pdev) err_clk_dis: clk_disable_unprepare(id->clk); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_disable(&pdev->dev); return ret; } @@ -984,6 +1002,7 @@ static int cdns_i2c_remove(struct platform_device *pdev) i2c_del_adapter(&id->adap); clk_notifier_unregister(id->clk, &id->clk_rate_change_nb); clk_disable_unprepare(id->clk); + pm_runtime_disable(&pdev->dev); return 0; } |