From: Boris Brezillon Date: Tue, 14 Jun 2016 09:13:14 +0000 (+0200) Subject: UPSTREAM: pwm: rockchip: Add support for atomic update X-Git-Tag: firefly_0821_release~418 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d86d501a10d7ae885b2d9d02943ae742acda686d;p=firefly-linux-kernel-4.4.55.git UPSTREAM: pwm: rockchip: Add support for atomic update Implement the ->apply() function to add support for atomic update. Signed-off-by: Boris Brezillon Tested-by: Heiko Stuebner Reviewed-by: Brian Norris Tested-by: Brian Norris Signed-off-by: Thierry Reding (commit 2bf1c98aa5a41651f5e6455117ff06f66ff3cc50) Conflicts: drivers/pwm/pwm-rockchip.c Change-Id: I92745cf301c26d20da284da8234e244828598d52 Signed-off-by: David Wu --- diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c index 52592643f3a6..186019318738 100644 --- a/drivers/pwm/pwm-rockchip.c +++ b/drivers/pwm/pwm-rockchip.c @@ -49,10 +49,12 @@ struct rockchip_pwm_regs { struct rockchip_pwm_data { struct rockchip_pwm_regs regs; unsigned int prescaler; + bool supports_polarity; const struct pwm_ops *ops; void (*set_enable)(struct pwm_chip *chip, - struct pwm_device *pwm, bool enable); + struct pwm_device *pwm, bool enable, + enum pwm_polarity polarity); void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state); }; @@ -63,7 +65,8 @@ static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c) } static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip, - struct pwm_device *pwm, bool enable) + struct pwm_device *pwm, bool enable, + enum pwm_polarity polarity) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN; @@ -93,14 +96,15 @@ static void rockchip_pwm_get_state_v1(struct pwm_chip *chip, } static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, - struct pwm_device *pwm, bool enable) + struct pwm_device *pwm, bool enable, + enum pwm_polarity polarity) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE | PWM_CONTINUOUS; u32 val; - if (pwm_get_polarity(pwm) == PWM_POLARITY_INVERSED) + if (polarity == PWM_POLARITY_INVERSED) enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE; else enable_conf |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE; @@ -185,15 +189,8 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, div = clk_rate * duty_ns; duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC); - ret = clk_enable(pc->pclk); - if (ret) - return ret; - writel(period, pc->base + pc->data->regs.period); writel(duty, pc->base + pc->data->regs.duty); - writel(0, pc->base + pc->data->regs.cntr); - - clk_disable(pc->pclk); #ifdef CONFIG_FB_ROCKCHIP if (!pc->data->regs.ctrl) { @@ -206,60 +203,65 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } -static int rockchip_pwm_set_polarity(struct pwm_chip *chip, - struct pwm_device *pwm, - enum pwm_polarity polarity) -{ - /* - * No action needed here because pwm->polarity will be set by the core - * and the core will only change polarity when the PWM is not enabled. - * We'll handle things in set_enable(). - */ - - return 0; -} - -static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + struct pwm_state curstate; + bool enabled; int ret; - ret = clk_enable(pc->clk); + pwm_get_state(pwm, &curstate); + enabled = curstate.enabled; + + ret = clk_enable(pc->pclk); if (ret) return ret; - ret = clk_enable(pc->pclk); + + ret = clk_enable(pc->clk); if (ret) return ret; - pc->data->set_enable(chip, pwm, true); + if (state->polarity != curstate.polarity && enabled) { + pc->data->set_enable(chip, pwm, false, state->polarity); + enabled = false; + } - return 0; -} + ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period); + if (ret) { + if (enabled != curstate.enabled) + pc->data->set_enable(chip, pwm, !enabled, + state->polarity); -static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + goto out; + } - pc->data->set_enable(chip, pwm, false); + if (state->enabled != enabled) + pc->data->set_enable(chip, pwm, state->enabled, + state->polarity); - clk_disable(pc->pclk); + /* + * Update the state with the real hardware, which can differ a bit + * because of period/duty_cycle approximation. + */ + rockchip_pwm_get_state(chip, pwm, state); + +out: clk_disable(pc->clk); + clk_disable(pc->pclk); + + return ret; } static const struct pwm_ops rockchip_pwm_ops_v1 = { .get_state = rockchip_pwm_get_state, - .config = rockchip_pwm_config, - .enable = rockchip_pwm_enable, - .disable = rockchip_pwm_disable, + .apply = rockchip_pwm_apply, .owner = THIS_MODULE, }; static const struct pwm_ops rockchip_pwm_ops_v2 = { .get_state = rockchip_pwm_get_state, - .config = rockchip_pwm_config, - .set_polarity = rockchip_pwm_set_polarity, - .enable = rockchip_pwm_enable, - .disable = rockchip_pwm_disable, + .apply = rockchip_pwm_apply, .owner = THIS_MODULE, }; @@ -284,6 +286,7 @@ static const struct rockchip_pwm_data pwm_data_v2 = { .ctrl = 0x0c, }, .prescaler = 1, + .supports_polarity = true, .ops = &rockchip_pwm_ops_v2, .set_enable = rockchip_pwm_set_enable_v2, .get_state = rockchip_pwm_get_state_v2, @@ -297,6 +300,7 @@ static const struct rockchip_pwm_data pwm_data_vop = { .ctrl = 0x00, }, .prescaler = 1, + .supports_polarity = true, .ops = &rockchip_pwm_ops_v2, .set_enable = rockchip_pwm_set_enable_v2, .get_state = rockchip_pwm_get_state_v2, @@ -343,26 +347,26 @@ static int rockchip_pwm_probe(struct platform_device *pdev) if (IS_ERR(pc->clk)) { ret = PTR_ERR(pc->clk); if (ret != -EPROBE_DEFER) - dev_err(&pdev->dev, "Can't get pwm clk: %d\n", ret); + dev_err(&pdev->dev, "Can't get bus clk: %d\n", ret); return ret; } if (IS_ERR(pc->pclk)) { ret = PTR_ERR(pc->pclk); if (ret != -EPROBE_DEFER) - dev_err(&pdev->dev, "Can't get pclk: %d\n", ret); + dev_err(&pdev->dev, "Can't get periph clk: %d\n", ret); return ret; } ret = clk_prepare_enable(pc->clk); if (ret) { - dev_err(&pdev->dev, "Can't prepare pwm clk: %d\n", ret); + dev_err(&pdev->dev, "Can't prepare bus clk: %d\n", ret); return ret; } ret = clk_prepare_enable(pc->pclk); if (ret) { - dev_err(&pdev->dev, "Can't prepare pclk: %d\n", ret); + dev_err(&pdev->dev, "Can't prepare periph clk: %d\n", ret); goto err_clk; } @@ -374,7 +378,7 @@ static int rockchip_pwm_probe(struct platform_device *pdev) pc->chip.base = -1; pc->chip.npwm = 1; - if (pc->data->ops->set_polarity) { + if (pc->data->supports_polarity) { pc->chip.of_xlate = of_pwm_xlate_with_flags; pc->chip.of_pwm_n_cells = 3; }