diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-xiic.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-xiic.c | 88 |
1 files changed, 81 insertions, 7 deletions
diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c index 6efd20095..74f54f2f4 100644 --- a/drivers/i2c/busses/i2c-xiic.c +++ b/drivers/i2c/busses/i2c-xiic.c @@ -37,6 +37,8 @@ #include <linux/io.h> #include <linux/slab.h> #include <linux/of.h> +#include <linux/clk.h> +#include <linux/pm_runtime.h> #define DRIVER_NAME "xiic-i2c" @@ -66,6 +68,7 @@ enum xiic_endian { * @endianness: big/little-endian byte order */ struct xiic_i2c { + struct device *dev; void __iomem *base; wait_queue_head_t wait; struct i2c_adapter adap; @@ -77,6 +80,7 @@ struct xiic_i2c { struct i2c_msg *rx_msg; int rx_pos; enum xiic_endian endianness; + struct clk *clk; }; @@ -164,6 +168,7 @@ struct xiic_i2c { #define XIIC_RESET_MASK 0xAUL +#define XIIC_PM_TIMEOUT 1000 /* ms */ /* * The following constant is used for the device global interrupt enable * register, to enable all interrupts for the device, this is the only bit @@ -676,9 +681,13 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) dev_dbg(adap->dev.parent, "%s entry SR: 0x%x\n", __func__, xiic_getreg8(i2c, XIIC_SR_REG_OFFSET)); + err = pm_runtime_get_sync(i2c->dev); + if (err < 0) + return err; + err = xiic_busy(i2c); if (err) - return err; + goto out; i2c->tx_msg = msgs; i2c->nmsgs = num; @@ -686,14 +695,20 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) xiic_start_xfer(i2c); if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) || - (i2c->state == STATE_DONE), HZ)) - return (i2c->state == STATE_DONE) ? num : -EIO; - else { + (i2c->state == STATE_DONE), HZ)) { + err = (i2c->state == STATE_DONE) ? num : -EIO; + goto out; + } else { i2c->tx_msg = NULL; i2c->rx_msg = NULL; i2c->nmsgs = 0; - return -ETIMEDOUT; + err = -ETIMEDOUT; + goto out; } +out: + pm_runtime_mark_last_busy(i2c->dev); + pm_runtime_put_autosuspend(i2c->dev); + return err; } static u32 xiic_func(struct i2c_adapter *adap) @@ -748,13 +763,28 @@ static int xiic_i2c_probe(struct platform_device *pdev) mutex_init(&i2c->lock); init_waitqueue_head(&i2c->wait); + i2c->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "input clock not found.\n"); + return PTR_ERR(i2c->clk); + } + ret = clk_prepare_enable(i2c->clk); + if (ret) { + dev_err(&pdev->dev, "Unable to enable clock.\n"); + return ret; + } + i2c->dev = &pdev->dev; + pm_runtime_enable(i2c->dev); + pm_runtime_set_autosuspend_delay(i2c->dev, XIIC_PM_TIMEOUT); + pm_runtime_use_autosuspend(i2c->dev); + pm_runtime_set_active(i2c->dev); ret = devm_request_threaded_irq(&pdev->dev, irq, xiic_isr, xiic_process, IRQF_ONESHOT, pdev->name, i2c); if (ret < 0) { dev_err(&pdev->dev, "Cannot claim IRQ\n"); - return ret; + goto err_clk_dis; } /* @@ -776,7 +806,7 @@ static int xiic_i2c_probe(struct platform_device *pdev) if (ret) { dev_err(&pdev->dev, "Failed to add adapter\n"); xiic_deinit(i2c); - return ret; + goto err_clk_dis; } if (pdata) { @@ -786,16 +816,30 @@ static int xiic_i2c_probe(struct platform_device *pdev) } return 0; + +err_clk_dis: + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_disable(&pdev->dev); + clk_disable_unprepare(i2c->clk); + return ret; } static int xiic_i2c_remove(struct platform_device *pdev) { struct xiic_i2c *i2c = platform_get_drvdata(pdev); + int ret; /* remove adapter & data */ i2c_del_adapter(&i2c->adap); + ret = clk_prepare_enable(i2c->clk); + if (ret) { + dev_err(&pdev->dev, "Unable to enable clock.\n"); + return ret; + } xiic_deinit(i2c); + clk_disable_unprepare(i2c->clk); + pm_runtime_disable(&pdev->dev); return 0; } @@ -808,12 +852,42 @@ static const struct of_device_id xiic_of_match[] = { MODULE_DEVICE_TABLE(of, xiic_of_match); #endif +static int __maybe_unused cdns_i2c_runtime_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct xiic_i2c *i2c = platform_get_drvdata(pdev); + + clk_disable(i2c->clk); + + return 0; +} + +static int __maybe_unused cdns_i2c_runtime_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct xiic_i2c *i2c = platform_get_drvdata(pdev); + int ret; + + ret = clk_enable(i2c->clk); + if (ret) { + dev_err(dev, "Cannot enable clock.\n"); + return ret; + } + + return 0; +} + +static const struct dev_pm_ops xiic_dev_pm_ops = { + SET_RUNTIME_PM_OPS(cdns_i2c_runtime_suspend, + cdns_i2c_runtime_resume, NULL) +}; static struct platform_driver xiic_i2c_driver = { .probe = xiic_i2c_probe, .remove = xiic_i2c_remove, .driver = { .name = DRIVER_NAME, .of_match_table = of_match_ptr(xiic_of_match), + .pm = &xiic_dev_pm_ops, }, }; |