[PATCH 52/58] PWM: atmel-tcb: switch to new binding

From: Alexandre Belloni
Date: Tue May 30 2017 - 17:55:59 EST

The PWM is now a subnode of the used TCB. This is cleaner and it mainly
allows to stop wasting TCB channels when only 4 PWMs are used.

Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
Cc: linux-pwm@xxxxxxxxxxxxxxx
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
drivers/pwm/Kconfig | 3 +-
drivers/pwm/pwm-atmel-tcb.c | 221 ++++++++++++++++++++++++--------------------
2 files changed, 122 insertions(+), 102 deletions(-)

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 313c10789ca2..d154f1fb610e 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -64,7 +64,8 @@ config PWM_ATMEL_HLCDC_PWM

config PWM_ATMEL_TCB
tristate "Atmel TC Block PWM support"
- depends on ATMEL_TCLIB && OF
+ depends on OF
+ select REGMAP_MMIO
help
Generic PWM framework driver for Atmel Timer Counter Block.

diff --git a/drivers/pwm/pwm-atmel-tcb.c b/drivers/pwm/pwm-atmel-tcb.c
index 75db585a2a94..9aa569835b97 100644
--- a/drivers/pwm/pwm-atmel-tcb.c
+++ b/drivers/pwm/pwm-atmel-tcb.c
@@ -16,19 +16,26 @@
#include <linux/err.h>
#include <linux/ioport.h>
#include <linux/io.h>
+#include <linux/mfd/syscon.h>
#include <linux/platform_device.h>
-#include <linux/atmel_tc.h>
#include <linux/pwm.h>
#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/regmap.h>
#include <linux/slab.h>
+#include <soc/at91/atmel_tcb.h>

-#define NPWM 6
+#define NPWM 2

-#define ATMEL_TC_ACMR_MASK (ATMEL_TC_ACPA | ATMEL_TC_ACPC | \
- ATMEL_TC_AEEVT | ATMEL_TC_ASWTRG)
+#define ATMEL_TC_ACMR_MASK (ATMEL_TC_CMR_ACPA_MSK | \
+ ATMEL_TC_CMR_ACPC_MSK | \
+ ATMEL_TC_CMR_AEEVT_MSK | \
+ ATMEL_TC_CMR_ASWTRG_MSK)

-#define ATMEL_TC_BCMR_MASK (ATMEL_TC_BCPB | ATMEL_TC_BCPC | \
- ATMEL_TC_BEEVT | ATMEL_TC_BSWTRG)
+#define ATMEL_TC_BCMR_MASK (ATMEL_TC_CMR_BCPB_MSK | \
+ ATMEL_TC_CMR_BCPC_MSK | \
+ ATMEL_TC_CMR_BEEVT_MSK | \
+ ATMEL_TC_CMR_BSWTRG_MSK)

struct atmel_tcb_pwm_device {
enum pwm_polarity polarity; /* PWM polarity */
@@ -40,7 +47,11 @@ struct atmel_tcb_pwm_device {
struct atmel_tcb_pwm_chip {
struct pwm_chip chip;
spinlock_t lock;
- struct atmel_tc *tc;
+ u8 channel;
+ u8 width;
+ struct regmap *regmap;
+ struct clk *clk;
+ struct clk *slow_clk;
struct atmel_tcb_pwm_device *pwms[NPWM];
};

@@ -65,10 +76,6 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip,
{
struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
struct atmel_tcb_pwm_device *tcbpwm;
- struct atmel_tc *tc = tcbpwmc->tc;
- void __iomem *regs = tc->regs;
- unsigned group = pwm->hwpwm / 2;
- unsigned index = pwm->hwpwm % 2;
unsigned cmr;
int ret;

@@ -76,7 +83,7 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip,
if (!tcbpwm)
return -ENOMEM;

- ret = clk_prepare_enable(tc->clk[group]);
+ ret = clk_prepare_enable(tcbpwmc->clk);
if (ret) {
devm_kfree(chip->dev, tcbpwm);
return ret;
@@ -89,28 +96,32 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip,
tcbpwm->div = 0;

spin_lock(&tcbpwmc->lock);
- cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR));
+ regmap_read(tcbpwmc->regmap, ATMEL_TC_CMR(tcbpwmc->channel), &cmr);
/*
* Get init config from Timer Counter registers if
* Timer Counter is already configured as a PWM generator.
*/
- if (cmr & ATMEL_TC_WAVE) {
- if (index == 0)
- tcbpwm->duty =
- __raw_readl(regs + ATMEL_TC_REG(group, RA));
+ if (cmr & ATMEL_TC_CMR_WAVE) {
+ if (pwm->hwpwm == 0)
+ regmap_read(tcbpwmc->regmap,
+ ATMEL_TC_RA(tcbpwmc->channel),
+ &tcbpwm->duty);
else
- tcbpwm->duty =
- __raw_readl(regs + ATMEL_TC_REG(group, RB));
-
- tcbpwm->div = cmr & ATMEL_TC_TCCLKS;
- tcbpwm->period = __raw_readl(regs + ATMEL_TC_REG(group, RC));
- cmr &= (ATMEL_TC_TCCLKS | ATMEL_TC_ACMR_MASK |
+ regmap_read(tcbpwmc->regmap,
+ ATMEL_TC_RB(tcbpwmc->channel),
+ &tcbpwm->duty);
+
+ tcbpwm->div = cmr & ATMEL_TC_CMR_TCLKS_MSK;
+ regmap_read(tcbpwmc->regmap, ATMEL_TC_RC(tcbpwmc->channel),
+ &tcbpwm->period);
+ cmr &= (ATMEL_TC_CMR_TCLKS_MSK | ATMEL_TC_ACMR_MASK |
ATMEL_TC_BCMR_MASK);
} else
cmr = 0;

- cmr |= ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO | ATMEL_TC_EEVT_XC0;
- __raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR));
+ cmr |= ATMEL_TC_CMR_WAVE | ATMEL_TC_CMR_WAVESEL_UPRC |
+ ATMEL_TC_CMR_EEVT_XC(0);
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_CMR(tcbpwmc->channel), cmr);
spin_unlock(&tcbpwmc->lock);

tcbpwmc->pwms[pwm->hwpwm] = tcbpwm;
@@ -122,9 +133,8 @@ static void atmel_tcb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
- struct atmel_tc *tc = tcbpwmc->tc;

- clk_disable_unprepare(tc->clk[pwm->hwpwm / 2]);
+ clk_disable_unprepare(tcbpwmc->clk);
tcbpwmc->pwms[pwm->hwpwm] = NULL;
devm_kfree(chip->dev, tcbpwm);
}
@@ -133,10 +143,6 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
- struct atmel_tc *tc = tcbpwmc->tc;
- void __iomem *regs = tc->regs;
- unsigned group = pwm->hwpwm / 2;
- unsigned index = pwm->hwpwm % 2;
unsigned cmr;
enum pwm_polarity polarity = tcbpwm->polarity;

@@ -152,35 +158,35 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
polarity = !polarity;

spin_lock(&tcbpwmc->lock);
- cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR));
+ regmap_read(tcbpwmc->regmap, ATMEL_TC_CMR(tcbpwmc->channel), &cmr);

/* flush old setting and set the new one */
- if (index == 0) {
+ if (pwm->hwpwm == 0) {
cmr &= ~ATMEL_TC_ACMR_MASK;
if (polarity == PWM_POLARITY_INVERSED)
- cmr |= ATMEL_TC_ASWTRG_CLEAR;
+ cmr |= ATMEL_TC_CMR_ASWTRG(CLEAR);
else
- cmr |= ATMEL_TC_ASWTRG_SET;
+ cmr |= ATMEL_TC_CMR_ASWTRG(SET);
} else {
cmr &= ~ATMEL_TC_BCMR_MASK;
if (polarity == PWM_POLARITY_INVERSED)
- cmr |= ATMEL_TC_BSWTRG_CLEAR;
+ cmr |= ATMEL_TC_CMR_BSWTRG(CLEAR);
else
- cmr |= ATMEL_TC_BSWTRG_SET;
+ cmr |= ATMEL_TC_CMR_BSWTRG(SET);
}

- __raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR));
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_CMR(tcbpwmc->channel), cmr);

/*
* Use software trigger to apply the new setting.
* If both PWM devices in this group are disabled we stop the clock.
*/
- if (!(cmr & (ATMEL_TC_ACPC | ATMEL_TC_BCPC)))
- __raw_writel(ATMEL_TC_SWTRG | ATMEL_TC_CLKDIS,
- regs + ATMEL_TC_REG(group, CCR));
+ if (!(cmr & (ATMEL_TC_CMR_ACPC_MSK | ATMEL_TC_CMR_BCPC_MSK)))
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_CCR(tcbpwmc->channel),
+ ATMEL_TC_CCR_SWTRG | ATMEL_TC_CCR_CLKDIS);
else
- __raw_writel(ATMEL_TC_SWTRG, regs +
- ATMEL_TC_REG(group, CCR));
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_CCR(tcbpwmc->channel),
+ ATMEL_TC_CCR_SWTRG);

spin_unlock(&tcbpwmc->lock);
}
@@ -189,10 +195,6 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
- struct atmel_tc *tc = tcbpwmc->tc;
- void __iomem *regs = tc->regs;
- unsigned group = pwm->hwpwm / 2;
- unsigned index = pwm->hwpwm % 2;
u32 cmr;
enum pwm_polarity polarity = tcbpwm->polarity;

@@ -208,25 +210,25 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
polarity = !polarity;

spin_lock(&tcbpwmc->lock);
- cmr = __raw_readl(regs + ATMEL_TC_REG(group, CMR));
+ regmap_read(tcbpwmc->regmap, ATMEL_TC_CMR(tcbpwmc->channel), &cmr);

/* flush old setting and set the new one */
- cmr &= ~ATMEL_TC_TCCLKS;
+ cmr &= ~ATMEL_TC_CMR_TCLKS_MSK;

- if (index == 0) {
+ if (pwm->hwpwm == 0) {
cmr &= ~ATMEL_TC_ACMR_MASK;

/* Set CMR flags according to given polarity */
if (polarity == PWM_POLARITY_INVERSED)
- cmr |= ATMEL_TC_ASWTRG_CLEAR;
+ cmr |= ATMEL_TC_CMR_ASWTRG(CLEAR);
else
- cmr |= ATMEL_TC_ASWTRG_SET;
+ cmr |= ATMEL_TC_CMR_ASWTRG(SET);
} else {
cmr &= ~ATMEL_TC_BCMR_MASK;
if (polarity == PWM_POLARITY_INVERSED)
- cmr |= ATMEL_TC_BSWTRG_CLEAR;
+ cmr |= ATMEL_TC_CMR_BSWTRG(CLEAR);
else
- cmr |= ATMEL_TC_BSWTRG_SET;
+ cmr |= ATMEL_TC_CMR_BSWTRG(SET);
}

/*
@@ -236,33 +238,40 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
* this config till next config call.
*/
if (tcbpwm->duty != tcbpwm->period && tcbpwm->duty > 0) {
- if (index == 0) {
+ if (pwm->hwpwm == 0) {
if (polarity == PWM_POLARITY_INVERSED)
- cmr |= ATMEL_TC_ACPA_SET | ATMEL_TC_ACPC_CLEAR;
+ cmr |= ATMEL_TC_CMR_ACPA(SET) |
+ ATMEL_TC_CMR_ACPC(CLEAR);
else
- cmr |= ATMEL_TC_ACPA_CLEAR | ATMEL_TC_ACPC_SET;
+ cmr |= ATMEL_TC_CMR_ACPA(CLEAR) |
+ ATMEL_TC_CMR_ACPC(SET);
} else {
if (polarity == PWM_POLARITY_INVERSED)
- cmr |= ATMEL_TC_BCPB_SET | ATMEL_TC_BCPC_CLEAR;
+ cmr |= ATMEL_TC_CMR_BCPB(SET) |
+ ATMEL_TC_CMR_BCPC(CLEAR);
else
- cmr |= ATMEL_TC_BCPB_CLEAR | ATMEL_TC_BCPC_SET;
+ cmr |= ATMEL_TC_CMR_BCPB(CLEAR) |
+ ATMEL_TC_CMR_BCPC(SET);
}
}

- cmr |= (tcbpwm->div & ATMEL_TC_TCCLKS);
+ cmr |= (tcbpwm->div & ATMEL_TC_CMR_TCLKS_MSK);

- __raw_writel(cmr, regs + ATMEL_TC_REG(group, CMR));
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_CMR(tcbpwmc->channel), cmr);

- if (index == 0)
- __raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RA));
+ if (pwm->hwpwm == 0)
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_RA(tcbpwmc->channel),
+ tcbpwm->duty);
else
- __raw_writel(tcbpwm->duty, regs + ATMEL_TC_REG(group, RB));
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_RB(tcbpwmc->channel),
+ tcbpwm->duty);

- __raw_writel(tcbpwm->period, regs + ATMEL_TC_REG(group, RC));
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_RC(tcbpwmc->channel),
+ tcbpwm->period);

/* Use software trigger to apply the new setting */
- __raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG,
- regs + ATMEL_TC_REG(group, CCR));
+ regmap_write(tcbpwmc->regmap, ATMEL_TC_CCR(tcbpwmc->channel),
+ ATMEL_TC_CCR_SWTRG | ATMEL_TC_CCR_CLKEN);
spin_unlock(&tcbpwmc->lock);
return 0;
}
@@ -272,15 +281,12 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
{
struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip);
struct atmel_tcb_pwm_device *tcbpwm = pwm_get_chip_data(pwm);
- unsigned group = pwm->hwpwm / 2;
- unsigned index = pwm->hwpwm % 2;
struct atmel_tcb_pwm_device *atcbpwm = NULL;
- struct atmel_tc *tc = tcbpwmc->tc;
int i;
int slowclk = 0;
unsigned period;
unsigned duty;
- unsigned rate = clk_get_rate(tc->clk[group]);
+ unsigned rate = clk_get_rate(tcbpwmc->clk);
unsigned long long min;
unsigned long long max;

@@ -294,7 +300,7 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
continue;
}
min = div_u64((u64)NSEC_PER_SEC * atmel_tc_divisors[i], rate);
- max = min << tc->tcb_config->counter_width;
+ max = min << tcbpwmc->width;
if (max >= period_ns)
break;
}
@@ -305,9 +311,9 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
*/
if (i == 5) {
i = slowclk;
- rate = clk_get_rate(tc->slow_clk);
+ rate = clk_get_rate(tcbpwmc->slow_clk);
min = div_u64(NSEC_PER_SEC, rate);
- max = min << tc->tcb_config->counter_width;
+ max = min << tcbpwmc->width;

/* If period is too big return ERANGE error */
if (max < period_ns)
@@ -317,17 +323,13 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
duty = div_u64(duty_ns, min);
period = div_u64(period_ns, min);

- if (index == 0)
- atcbpwm = tcbpwmc->pwms[pwm->hwpwm + 1];
+ if (pwm->hwpwm == 0)
+ atcbpwm = tcbpwmc->pwms[1];
else
- atcbpwm = tcbpwmc->pwms[pwm->hwpwm - 1];
+ atcbpwm = tcbpwmc->pwms[0];

/*
- * PWM devices provided by TCB driver are grouped by 2:
- * - group 0: PWM 0 & 1
- * - group 1: PWM 2 & 3
- * - group 2: PWM 4 & 5
- *
+ * PWM devices provided by the TCB driver are grouped by 2.
* PWM devices in a given group must be configured with the
* same period_ns.
*
@@ -365,31 +367,41 @@ static const struct pwm_ops atmel_tcb_pwm_ops = {

static int atmel_tcb_pwm_probe(struct platform_device *pdev)
{
+ const struct of_device_id *match;
+ const struct atmel_tcb_info *tcb_info;
struct atmel_tcb_pwm_chip *tcbpwm;
struct device_node *np = pdev->dev.of_node;
- struct atmel_tc *tc;
+ struct regmap *regmap;
+ struct clk *clk;
+ struct clk *slow_clk;
int err;
- int tcblock;
+ int channel;

- err = of_property_read_u32(np, "tc-block", &tcblock);
+ err = of_property_read_u32(np, "reg", &channel);
if (err < 0) {
dev_err(&pdev->dev,
- "failed to get Timer Counter Block number from device tree (error: %d)\n",
+ "failed to get Timer Counter Block channel from device tree (error: %d)\n",
err);
return err;
}

- tc = atmel_tc_alloc(tcblock);
- if (tc == NULL) {
- dev_err(&pdev->dev, "failed to allocate Timer Counter Block\n");
- return -ENOMEM;
- }
+ regmap = syscon_node_to_regmap(np->parent);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ slow_clk = of_clk_get_by_name(np->parent, "slow_clk");
+ if (IS_ERR(slow_clk))
+ return PTR_ERR(slow_clk);
+
+ clk = tcb_clk_get(np, channel);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);

tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL);
if (tcbpwm == NULL) {
err = -ENOMEM;
dev_err(&pdev->dev, "failed to allocate memory\n");
- goto err_free_tc;
+ goto err_slow_clk;
}

tcbpwm->chip.dev = &pdev->dev;
@@ -398,11 +410,18 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev)
tcbpwm->chip.of_pwm_n_cells = 3;
tcbpwm->chip.base = -1;
tcbpwm->chip.npwm = NPWM;
- tcbpwm->tc = tc;
+ tcbpwm->channel = channel;
+ tcbpwm->regmap = regmap;
+ tcbpwm->clk = clk;
+ tcbpwm->slow_clk = slow_clk;

- err = clk_prepare_enable(tc->slow_clk);
+ match = of_match_node(atmel_tcb_dt_ids, np->parent);
+ tcb_info = match->data;
+ tcbpwm->width = tcb_info->bits;
+
+ err = clk_prepare_enable(slow_clk);
if (err)
- goto err_free_tc;
+ goto err_slow_clk;

spin_lock_init(&tcbpwm->lock);

@@ -415,10 +434,10 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev)
return 0;

err_disable_clk:
- clk_disable_unprepare(tcbpwm->tc->slow_clk);
+ clk_disable_unprepare(tcbpwm->slow_clk);

-err_free_tc:
- atmel_tc_free(tc);
+err_slow_clk:
+ clk_put(slow_clk);

return err;
}
@@ -428,14 +447,14 @@ static int atmel_tcb_pwm_remove(struct platform_device *pdev)
struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev);
int err;

- clk_disable_unprepare(tcbpwm->tc->slow_clk);
+ clk_disable_unprepare(tcbpwm->slow_clk);
+ clk_put(tcbpwm->slow_clk);
+ clk_put(tcbpwm->clk);

err = pwmchip_remove(&tcbpwm->chip);
if (err < 0)
return err;

- atmel_tc_free(tcbpwm->tc);
-
return 0;
}

--
2.11.0