Re: [PATCH v4 2/2] pwm: rockchip: Added to support for RK3288 SoC
From: caesar
Date: Thu Aug 07 2014 - 09:04:44 EST
Thierry,
å 2014å08æ07æ 14:18, Thierry Reding åé:
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.
As you say, I will rewrite the about if it's really need do so it.
For example:
static const struct rockchip_pwm_data pwm_data_v1 = {
.regs = {
.duty = 0x04,
.period = 0x08,
.cntr = 0x00,
.ctrl = 0x0c,
},
.prescaler = 2,
.set_enable = rockchip_pwm_set_enable_v1,
};
static const struct rockchip_pwm_data pwm_data_v2 = {
.regs = {
.duty = 0x08,
.period = 0x04,
.cntr = 0x00,
.ctrl = 0x0c,
},
.prescaler = 1,
.set_enable = rockchip_pwm_set_enable_v2,
};
static const struct rockchip_pwm_data pwm_data_vop = {
.regs = {
.duty = 0x08,
.period = 0x04,
.cntr = 0x0c,
.ctrl = 0x00,
},
.prescaler = 1,
.set_enable = rockchip_pwm_set_enable_v2,
};
Is that right?
+ .set_enable = rockchip_pwm_set_enable_v2,
+};
No need for the double indirection.
Sorry, I think is need if you mean a double indirection for ".set_enable".
Caesar
Thierry
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/