On Thu, Jul 24, 2014 at 06:21:35PM +0800, Caesar Wang wrote:
> This patch added to support the PWM controller found on
> RK3288 SoC.
>
> Signed-off-by: Caesar Wang <caesar.wang@xxxxxxxxxxxxxx>
> ---
> drivers/pwm/pwm-rockchip.c | 124 ++++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 105 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
> index eec2145..59c2513 100644
> --- a/drivers/pwm/pwm-rockchip.c
> +++ b/drivers/pwm/pwm-rockchip.c
> @@ -2,6 +2,7 @@
> * PWM driver for Rockchip SoCs
> *
> * Copyright (C) 2014 Beniamino Galvani <b.galvani@xxxxxxxxx>
> + * Copyright (C) 2014 ROCKCHIP, Inc.
> *
> * This program is free software; you can redistribute it and/or
> * modify it under the terms of the GNU General Public License
> @@ -12,6 +13,7 @@
> #include <linux/io.h>
> #include <linux/module.h>
> #include <linux/of.h>
> +#include <linux/of_device.h>
> #include <linux/platform_device.h>
> #include <linux/pwm.h>
> #include <linux/time.h>
> @@ -25,17 +27,72 @@
>
> #define PRESCALER 2
>
> +#define PWM_ENABLE (1 << 0)
> +#define PWM_CONTINUOUS (1 << 1)
> +#define PWM_DUTY_POSITIVE (1 << 3)
> +#define PWM_INACTIVE_NEGATIVE (0 << 4)
> +#define PWM_OUTPUT_LEFT (0 << 5)
> +#define PWM_LP_DISABLE (0 << 8)
> +
> struct rockchip_pwm_chip {
> struct pwm_chip chip;
> struct clk *clk;
> + const struct rockchip_pwm_data *data;
> void __iomem *base;
> };
>
> +struct rockchip_pwm_regs {
> + unsigned long duty;
> + unsigned long period;
> + unsigned long cntr;
> + unsigned long ctrl;
> +};
> +
> +struct rockchip_pwm_data {
> + struct rockchip_pwm_regs regs;
> + unsigned int prescaler;
> +
> + void (*set_enable)(struct pwm_chip *chip, bool enable);
> +};
> +
> static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)
> {
> return container_of(c, struct rockchip_pwm_chip, chip);
> }
>
> +static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip, bool enable)
> +{
> + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
> + u32 val = 0;
> + u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
> +
> + val = readl_relaxed(pc->base + pc->data->regs.ctrl);
> +
> + if (enable)
> + val |= enable_conf;
> + else
> + val &= ~enable_conf;
> +
> + writel_relaxed(val, pc->base + pc->data->regs.ctrl);
> +}
> +
> +static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, bool enable)
> +{
> + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
> + u32 val = 0;
> + u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
> + PWM_CONTINUOUS | PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
> +
> + val = readl_relaxed(pc->base + pc->data->regs.ctrl);
> +
> + if (enable)
> + val |= enable_conf;
> + else
> + val &= ~enable_conf;
> +
> + writel_relaxed(val, pc->base + pc->data->regs.ctrl);
> +}
> +
> static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> int duty_ns, int period_ns)
> {
> @@ -52,20 +109,20 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> * default prescaler value for all practical clock rate values.
> */
> div = clk_rate * period_ns;
> - do_div(div, PRESCALER * NSEC_PER_SEC);
> + do_div(div, pc->data->prescaler * NSEC_PER_SEC);
> period = div;
>
> div = clk_rate * duty_ns;
> - do_div(div, PRESCALER * NSEC_PER_SEC);
> + do_div(div, pc->data->prescaler * NSEC_PER_SEC);
> duty = div;
>
> ret = clk_enable(pc->clk);
> if (ret)
> return ret;
>
> - writel(period, pc->base + PWM_LRC);
> - writel(duty, pc->base + PWM_HRC);
> - writel(0, pc->base + PWM_CNTR);
> + 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->clk);
>
> @@ -76,15 +133,12 @@ static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
> {
> struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
> int ret;
> - u32 val;
>
> ret = clk_enable(pc->clk);
> if (ret)
> return ret;
>
> - val = readl_relaxed(pc->base + PWM_CTRL);
> - val |= PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
> - writel_relaxed(val, pc->base + PWM_CTRL);
> + pc->data->set_enable(chip, true);
>
> return 0;
> }
> @@ -92,11 +146,8 @@ static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
> static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
> {
> struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
> - u32 val;
>
> - val = readl_relaxed(pc->base + PWM_CTRL);
> - val &= ~(PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN);
> - writel_relaxed(val, pc->base + PWM_CTRL);
> + pc->data->set_enable(chip, false);
>
> clk_disable(pc->clk);
> }
> @@ -108,12 +159,52 @@ static const struct pwm_ops rockchip_pwm_ops = {
> .owner = THIS_MODULE,
> };
>
> +static const struct rockchip_pwm_data pwm_data_v1 = {
> + .regs.duty = PWM_HRC,
> + .regs.period = PWM_LRC,
> + .regs.cntr = PWM_CNTR,
> + .regs.ctrl = PWM_CTRL,
Perhaps a slightly more idiomatic way to write this would be:
static const struct rockchip_pwm_data pwm_data_v1 = {
.regs = {
.duty = PWM_HRC,
.period = PWM_LRC,
.cntr = PWM_CNTR,
.ctrl = PWM_CTRL,
},
...
};
And similar for the v2 and vop structures. And like I said in another
reply, since the defines are now only used in this structure it's a
little redundant to give them symbolic names, so the above could equally
well be:
static const struct rockchip_pwm_data pwm_data_v1 = {
.regs = {
.duty = 0x04,
.period = 0x08,
.cntr = 0x00,
.ctrl = 0x0c,
},
...
};
> + .prescaler = PRESCALER,
Similarly for the prescaler value, it can now simply be 2 here.
> + .set_enable = rockchip_pwm_set_enable_v1,
> +};
> +
> +static const struct rockchip_pwm_data pwm_data_v2 = {
> + .regs.duty = PWM_LRC,
> + .regs.period = PWM_HRC,
> + .regs.cntr = PWM_CNTR,
> + .regs.ctrl = PWM_CTRL,
> + .prescaler = PRESCALER-1,
And 1 here.
> + .set_enable = rockchip_pwm_set_enable_v2,
> +};
> +
> +static const struct rockchip_pwm_data pwm_data_vop = {
> + .regs.duty = PWM_LRC,
> + .regs.period = PWM_HRC,
> + .regs.cntr = PWM_CTRL,
> + .regs.ctrl = PWM_CNTR,
> + .prescaler = PRESCALER-1,
And 1 here.
> + .set_enable = rockchip_pwm_set_enable_v2,
> +};
No need for the double indirection.
Thierry
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