From d4a4f927e4ddcf70320b03a6a687d55839721f7b Mon Sep 17 00:00:00 2001 From: Ajay Gupta Date: Fri, 7 Jun 2019 09:34:20 -0700 Subject: [PATCH] i2c: nvidia-gpu: add runtime pm support Enable runtime pm support with autosuspend delay of three second. This is to make sure I2C client device Cypress CCGx has completed all transaction. Signed-off-by: Ajay Gupta Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-nvidia-gpu.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-gpu.c index 7678a46..364244f 100644 --- a/drivers/i2c/busses/i2c-nvidia-gpu.c +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c @@ -176,6 +176,7 @@ static int gpu_i2c_master_xfer(struct i2c_adapter *adap, * The controller supports maximum 4 byte read due to known * limitation of sending STOP after every read. */ + pm_runtime_get_sync(i2cd->dev); for (i = 0; i < num; i++) { if (msgs[i].flags & I2C_M_RD) { /* program client address before starting read */ @@ -217,6 +218,8 @@ exit: if (status2 < 0) dev_err(i2cd->dev, "i2c stop failed %d\n", status2); } + pm_runtime_mark_last_busy(i2cd->dev); + pm_runtime_put_autosuspend(i2cd->dev); return status; } @@ -336,6 +339,11 @@ static int gpu_i2c_probe(struct pci_dev *pdev, const struct pci_device_id *id) goto del_adapter; } + pm_runtime_set_autosuspend_delay(&pdev->dev, 3000); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + pm_runtime_allow(&pdev->dev); + return 0; del_adapter: @@ -349,10 +357,21 @@ static void gpu_i2c_remove(struct pci_dev *pdev) { struct gpu_i2c_dev *i2cd = dev_get_drvdata(&pdev->dev); + pm_runtime_get_noresume(i2cd->dev); i2c_del_adapter(&i2cd->adapter); pci_free_irq_vectors(pdev); } +/* + * We need gpu_i2c_suspend() even if it is stub, for runtime pm to work + * correctly. Without it, lspci shows runtime pm status as "D0" for the card. + * Documentation/power/pci.txt also insists for driver to provide this. + */ +static __maybe_unused int gpu_i2c_suspend(struct device *dev) +{ + return 0; +} + static __maybe_unused int gpu_i2c_resume(struct device *dev) { struct gpu_i2c_dev *i2cd = dev_get_drvdata(dev); @@ -361,7 +380,8 @@ static __maybe_unused int gpu_i2c_resume(struct device *dev) return 0; } -static UNIVERSAL_DEV_PM_OPS(gpu_i2c_driver_pm, NULL, gpu_i2c_resume, NULL); +static UNIVERSAL_DEV_PM_OPS(gpu_i2c_driver_pm, gpu_i2c_suspend, gpu_i2c_resume, + NULL); static struct pci_driver gpu_i2c_driver = { .name = "nvidia-gpu", -- 2.7.4