diff options
Diffstat (limited to 'drivers/pwm/pwm-tegra.c')
-rw-r--r-- | drivers/pwm/pwm-tegra.c | 69 |
1 files changed, 52 insertions, 17 deletions
diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c index d4de0607b502..e4647840cd6e 100644 --- a/drivers/pwm/pwm-tegra.c +++ b/drivers/pwm/pwm-tegra.c @@ -26,9 +26,11 @@ #include <linux/io.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_device.h> #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 @@ -36,15 +38,20 @@ #define PWM_SCALE_WIDTH 13 #define PWM_SCALE_SHIFT 0 -#define NUM_PWM 4 +struct tegra_pwm_soc { + unsigned int num_channels; +}; struct tegra_pwm_chip { - struct pwm_chip chip; - struct device *dev; + struct pwm_chip chip; + struct device *dev; + + struct clk *clk; + struct reset_control*rst; - struct clk *clk; + void __iomem *regs; - void __iomem *mmio_base; + const struct tegra_pwm_soc *soc; }; static inline struct tegra_pwm_chip *to_tegra_pwm_chip(struct pwm_chip *chip) @@ -54,20 +61,20 @@ static inline struct tegra_pwm_chip *to_tegra_pwm_chip(struct pwm_chip *chip) static inline u32 pwm_readl(struct tegra_pwm_chip *chip, unsigned int num) { - return readl(chip->mmio_base + (num << 4)); + return readl(chip->regs + (num << 4)); } static inline void pwm_writel(struct tegra_pwm_chip *chip, unsigned int num, unsigned long val) { - writel(val, chip->mmio_base + (num << 4)); + writel(val, chip->regs + (num << 4)); } static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct tegra_pwm_chip *pc = to_tegra_pwm_chip(chip); - unsigned long long c; + unsigned long long c = duty_ns; unsigned long rate, hz; u32 val = 0; int err; @@ -77,7 +84,8 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * per (1 << PWM_DUTY_WIDTH) cycles and make sure to round to the * nearest integer during division. */ - c = duty_ns * ((1 << PWM_DUTY_WIDTH) - 1) + period_ns / 2; + c *= (1 << PWM_DUTY_WIDTH); + c += period_ns / 2; do_div(c, period_ns); val = (u32)c << PWM_DUTY_SHIFT; @@ -176,12 +184,13 @@ static int tegra_pwm_probe(struct platform_device *pdev) if (!pwm) return -ENOMEM; + pwm->soc = of_device_get_match_data(&pdev->dev); pwm->dev = &pdev->dev; r = platform_get_resource(pdev, IORESOURCE_MEM, 0); - pwm->mmio_base = devm_ioremap_resource(&pdev->dev, r); - if (IS_ERR(pwm->mmio_base)) - return PTR_ERR(pwm->mmio_base); + pwm->regs = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(pwm->regs)) + return PTR_ERR(pwm->regs); platform_set_drvdata(pdev, pwm); @@ -189,14 +198,24 @@ 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; - pwm->chip.npwm = NUM_PWM; + pwm->chip.npwm = pwm->soc->num_channels; 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; } @@ -206,12 +225,17 @@ static int tegra_pwm_probe(struct platform_device *pdev) static int tegra_pwm_remove(struct platform_device *pdev) { struct tegra_pwm_chip *pc = platform_get_drvdata(pdev); - int i; + unsigned int i; + int err; if (WARN_ON(!pc)) return -ENODEV; - for (i = 0; i < NUM_PWM; i++) { + 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]; if (!pwm_is_enabled(pwm)) @@ -223,12 +247,23 @@ 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); } +static const struct tegra_pwm_soc tegra20_pwm_soc = { + .num_channels = 4, +}; + +static const struct tegra_pwm_soc tegra186_pwm_soc = { + .num_channels = 1, +}; + static const struct of_device_id tegra_pwm_of_match[] = { - { .compatible = "nvidia,tegra20-pwm" }, - { .compatible = "nvidia,tegra30-pwm" }, + { .compatible = "nvidia,tegra20-pwm", .data = &tegra20_pwm_soc }, + { .compatible = "nvidia,tegra186-pwm", .data = &tegra186_pwm_soc }, { } }; |