diff options
| author | Rohith Seelaboyina <rseelaboyina@nvidia.com> | 2016-06-22 13:47:19 +0200 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2016-07-11 12:49:31 +0200 |
| commit | 5dfbd2bd5439f1ada5ddaa3883e9e038de5d2abe (patch) | |
| tree | 2a7d98e034a4e9d7f1194ad9f379de6597b44d0c | |
| parent | pwm: tegra: Rename mmio_base to regs (diff) | |
| download | linux-5dfbd2bd5439f1ada5ddaa3883e9e038de5d2abe.tar.xz linux-5dfbd2bd5439f1ada5ddaa3883e9e038de5d2abe.zip | |
pwm: tegra: Add support for reset control
Add reset control of the PWM controller to reset it before
accessing the PWM register.
Signed-off-by: Rohith Seelaboyina <rseelaboyina@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
| -rw-r--r-- | drivers/pwm/pwm-tegra.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c index 3cbb32d8064f..097658e0751b 100644 --- a/drivers/pwm/pwm-tegra.c +++ b/drivers/pwm/pwm-tegra.c @@ -29,6 +29,7 @@ #include <linux/pwm.h> #include <linux/platform_device.h> #include <linux/slab.h> +#include <linux/reset.h> #define PWM_ENABLE (1 << 31) #define PWM_DUTY_WIDTH 8 @@ -41,6 +42,7 @@ struct tegra_pwm_chip { struct device *dev; struct clk *clk; + struct reset_control*rst; void __iomem *regs; }; @@ -187,6 +189,15 @@ static int tegra_pwm_probe(struct platform_device *pdev) if (IS_ERR(pwm->clk)) return PTR_ERR(pwm->clk); + pwm->rst = devm_reset_control_get(&pdev->dev, "pwm"); + if (IS_ERR(pwm->rst)) { + ret = PTR_ERR(pwm->rst); + dev_err(&pdev->dev, "Reset control is not found: %d\n", ret); + return ret; + } + + reset_control_deassert(pwm->rst); + pwm->chip.dev = &pdev->dev; pwm->chip.ops = &tegra_pwm_ops; pwm->chip.base = -1; @@ -195,6 +206,7 @@ static int tegra_pwm_probe(struct platform_device *pdev) ret = pwmchip_add(&pwm->chip); if (ret < 0) { dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); + reset_control_assert(pwm->rst); return ret; } @@ -205,10 +217,15 @@ static int tegra_pwm_remove(struct platform_device *pdev) { struct tegra_pwm_chip *pc = platform_get_drvdata(pdev); unsigned int i; + int err; if (WARN_ON(!pc)) return -ENODEV; + err = clk_prepare_enable(pc->clk); + if (err < 0) + return err; + for (i = 0; i < pc->chip.npwm; i++) { struct pwm_device *pwm = &pc->chip.pwms[i]; @@ -221,6 +238,9 @@ static int tegra_pwm_remove(struct platform_device *pdev) clk_disable_unprepare(pc->clk); } + reset_control_assert(pc->rst); + clk_disable_unprepare(pc->clk); + return pwmchip_remove(&pc->chip); } |