diff options
Diffstat (limited to 'drivers/pwm/pwm-vt8500.c')
| -rw-r--r-- | drivers/pwm/pwm-vt8500.c | 87 |
1 files changed, 72 insertions, 15 deletions
diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c index f9de9b28e46..69effd19afc 100644 --- a/drivers/pwm/pwm-vt8500.c +++ b/drivers/pwm/pwm-vt8500.c @@ -36,6 +36,25 @@ */ #define VT8500_NR_PWMS 2 +#define REG_CTRL(pwm) (((pwm) << 4) + 0x00) +#define REG_SCALAR(pwm) (((pwm) << 4) + 0x04) +#define REG_PERIOD(pwm) (((pwm) << 4) + 0x08) +#define REG_DUTY(pwm) (((pwm) << 4) + 0x0C) +#define REG_STATUS 0x40 + +#define CTRL_ENABLE BIT(0) +#define CTRL_INVERT BIT(1) +#define CTRL_AUTOLOAD BIT(2) +#define CTRL_STOP_IMM BIT(3) +#define CTRL_LOAD_PRESCALE BIT(4) +#define CTRL_LOAD_PERIOD BIT(5) + +#define STATUS_CTRL_UPDATE BIT(0) +#define STATUS_SCALAR_UPDATE BIT(1) +#define STATUS_PERIOD_UPDATE BIT(2) +#define STATUS_DUTY_UPDATE BIT(3) +#define STATUS_ALL_UPDATE 0x0F + struct vt8500_chip { struct pwm_chip chip; void __iomem *base; @@ -45,15 +64,17 @@ struct vt8500_chip { #define to_vt8500_chip(chip) container_of(chip, struct vt8500_chip, chip) #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t) -static inline void pwm_busy_wait(void __iomem *reg, u8 bitmask) +static inline void pwm_busy_wait(struct vt8500_chip *vt8500, int nr, u8 bitmask) { int loops = msecs_to_loops(10); - while ((readb(reg) & bitmask) && --loops) + u32 mask = bitmask << (nr << 8); + + while ((readl(vt8500->base + REG_STATUS) & mask) && --loops) cpu_relax(); if (unlikely(!loops)) - pr_warn("Waiting for status bits 0x%x to clear timed out\n", - bitmask); + dev_warn(vt8500->chip.dev, "Waiting for status bits 0x%x to clear timed out\n", + mask); } static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, @@ -63,6 +84,7 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, unsigned long long c; unsigned long period_cycles, prescale, pv, dc; int err; + u32 val; err = clk_enable(vt8500->clk); if (err < 0) { @@ -91,14 +113,19 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, do_div(c, period_ns); dc = c; - pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 1)); - writel(prescale, vt8500->base + 0x4 + (pwm->hwpwm << 4)); + writel(prescale, vt8500->base + REG_SCALAR(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_SCALAR_UPDATE); - pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 2)); - writel(pv, vt8500->base + 0x8 + (pwm->hwpwm << 4)); + writel(pv, vt8500->base + REG_PERIOD(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_PERIOD_UPDATE); - pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 3)); - writel(dc, vt8500->base + 0xc + (pwm->hwpwm << 4)); + writel(dc, vt8500->base + REG_DUTY(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_DUTY_UPDATE); + + val = readl(vt8500->base + REG_CTRL(pwm->hwpwm)); + val |= CTRL_AUTOLOAD; + writel(val, vt8500->base + REG_CTRL(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE); clk_disable(vt8500->clk); return 0; @@ -106,8 +133,9 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { - int err; struct vt8500_chip *vt8500 = to_vt8500_chip(chip); + int err; + u32 val; err = clk_enable(vt8500->clk); if (err < 0) { @@ -115,25 +143,52 @@ static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) return err; } - pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 0)); - writel(5, vt8500->base + (pwm->hwpwm << 4)); + val = readl(vt8500->base + REG_CTRL(pwm->hwpwm)); + val |= CTRL_ENABLE; + writel(val, vt8500->base + REG_CTRL(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE); + return 0; } static void vt8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { struct vt8500_chip *vt8500 = to_vt8500_chip(chip); + u32 val; - pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 0)); - writel(0, vt8500->base + (pwm->hwpwm << 4)); + val = readl(vt8500->base + REG_CTRL(pwm->hwpwm)); + val &= ~CTRL_ENABLE; + writel(val, vt8500->base + REG_CTRL(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE); clk_disable(vt8500->clk); } +static int vt8500_pwm_set_polarity(struct pwm_chip *chip, + struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct vt8500_chip *vt8500 = to_vt8500_chip(chip); + u32 val; + + val = readl(vt8500->base + REG_CTRL(pwm->hwpwm)); + + if (polarity == PWM_POLARITY_INVERSED) + val |= CTRL_INVERT; + else + val &= ~CTRL_INVERT; + + writel(val, vt8500->base + REG_CTRL(pwm->hwpwm)); + pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE); + + return 0; +} + static struct pwm_ops vt8500_pwm_ops = { .enable = vt8500_pwm_enable, .disable = vt8500_pwm_disable, .config = vt8500_pwm_config, + .set_polarity = vt8500_pwm_set_polarity, .owner = THIS_MODULE, }; @@ -163,6 +218,8 @@ static int vt8500_pwm_probe(struct platform_device *pdev) chip->chip.dev = &pdev->dev; chip->chip.ops = &vt8500_pwm_ops; + chip->chip.of_xlate = of_pwm_xlate_with_flags; + chip->chip.of_pwm_n_cells = 3; chip->chip.base = -1; chip->chip.npwm = VT8500_NR_PWMS; |