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-rw-r--r--Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt9
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt18
-rw-r--r--drivers/pwm/Kconfig25
-rw-r--r--drivers/pwm/Makefile1
-rw-r--r--drivers/pwm/core.c2
-rw-r--r--drivers/pwm/pwm-bcm2835.c18
-rw-r--r--drivers/pwm/pwm-fsl-ftm.c58
-rw-r--r--drivers/pwm/pwm-lpc32xx.c59
-rw-r--r--drivers/pwm/pwm-lpss.c57
-rw-r--r--drivers/pwm/pwm-lpss.h1
-rw-r--r--drivers/pwm/pwm-omap-dmtimer.c327
-rw-r--r--drivers/pwm/pwm-rcar.c2
-rw-r--r--include/linux/platform_data/pwm_omap_dmtimer.h69
13 files changed, 539 insertions, 107 deletions
diff --git a/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt b/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt
index cfe1db3bb6e9..74b5bc5dd19a 100644
--- a/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt
+++ b/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt
@@ -6,7 +6,12 @@ Required properties:
Examples:
-pwm@0x4005C000 {
+pwm@4005c000 {
compatible = "nxp,lpc3220-pwm";
- reg = <0x4005C000 0x8>;
+ reg = <0x4005c000 0x4>;
+};
+
+pwm@4005c004 {
+ compatible = "nxp,lpc3220-pwm";
+ reg = <0x4005c004 0x4>;
};
diff --git a/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt b/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt
new file mode 100644
index 000000000000..5befb538db95
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt
@@ -0,0 +1,18 @@
+* OMAP PWM for dual-mode timers
+
+Required properties:
+- compatible: Shall contain "ti,omap-dmtimer-pwm".
+- ti,timers: phandle to PWM capable OMAP timer. See arm/omap/timer.txt for info
+ about these timers.
+- #pwm-cells: Should be 3. See pwm.txt in this directory for a description of
+ the cells format.
+
+Optional properties:
+- ti,prescaler: Should be a value between 0 and 7, see the timers datasheet
+
+Example:
+ pwm9: dmtimer-pwm@9 {
+ compatible = "ti,omap-dmtimer-pwm";
+ ti,timers = <&timer9>;
+ #pwm-cells = <3>;
+ };
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 2f4641a0e88b..8cf0dae78555 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -148,6 +148,7 @@ config PWM_EP93XX
config PWM_FSL_FTM
tristate "Freescale FlexTimer Module (FTM) PWM support"
+ depends on HAS_IOMEM
depends on OF
select REGMAP_MMIO
help
@@ -222,18 +223,12 @@ config PWM_LPC32XX
will be called pwm-lpc32xx.
config PWM_LPSS
- tristate "Intel LPSS PWM support"
- depends on X86
- help
- Generic PWM framework driver for Intel Low Power Subsystem PWM
- controller.
-
- To compile this driver as a module, choose M here: the module
- will be called pwm-lpss.
+ tristate
config PWM_LPSS_PCI
tristate "Intel LPSS PWM PCI driver"
- depends on PWM_LPSS && PCI
+ depends on X86 && PCI
+ select PWM_LPSS
help
The PCI driver for Intel Low Power Subsystem PWM controller.
@@ -242,7 +237,8 @@ config PWM_LPSS_PCI
config PWM_LPSS_PLATFORM
tristate "Intel LPSS PWM platform driver"
- depends on PWM_LPSS && ACPI
+ depends on X86 && ACPI
+ select PWM_LPSS
help
The platform driver for Intel Low Power Subsystem PWM controller.
@@ -270,6 +266,15 @@ config PWM_MXS
To compile this driver as a module, choose M here: the module
will be called pwm-mxs.
+config PWM_OMAP_DMTIMER
+ tristate "OMAP Dual-Mode Timer PWM support"
+ depends on OF && ARCH_OMAP && OMAP_DM_TIMER
+ help
+ Generic PWM framework driver for OMAP Dual-Mode Timer PWM output
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-omap-dmtimer
+
config PWM_PCA9685
tristate "NXP PCA9685 PWM driver"
depends on I2C
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 69b8275f3c08..dd35bc121a18 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_PWM_LPSS_PCI) += pwm-lpss-pci.o
obj-$(CONFIG_PWM_LPSS_PLATFORM) += pwm-lpss-platform.o
obj-$(CONFIG_PWM_MTK_DISP) += pwm-mtk-disp.o
obj-$(CONFIG_PWM_MXS) += pwm-mxs.o
+obj-$(CONFIG_PWM_OMAP_DMTIMER) += pwm-omap-dmtimer.o
obj-$(CONFIG_PWM_PCA9685) += pwm-pca9685.o
obj-$(CONFIG_PWM_PUV3) += pwm-puv3.o
obj-$(CONFIG_PWM_PXA) += pwm-pxa.o
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index d24ca5f281b4..7831bc6b51dd 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -889,7 +889,7 @@ EXPORT_SYMBOL_GPL(devm_pwm_put);
*/
bool pwm_can_sleep(struct pwm_device *pwm)
{
- return pwm->chip->can_sleep;
+ return true;
}
EXPORT_SYMBOL_GPL(pwm_can_sleep);
diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c
index b4c7f956b6fa..c5dbf16d810b 100644
--- a/drivers/pwm/pwm-bcm2835.c
+++ b/drivers/pwm/pwm-bcm2835.c
@@ -29,7 +29,6 @@
struct bcm2835_pwm {
struct pwm_chip chip;
struct device *dev;
- unsigned long scaler;
void __iomem *base;
struct clk *clk;
};
@@ -66,6 +65,15 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+ unsigned long rate = clk_get_rate(pc->clk);
+ unsigned long scaler;
+
+ if (!rate) {
+ dev_err(pc->dev, "failed to get clock rate\n");
+ return -EINVAL;
+ }
+
+ scaler = NSEC_PER_SEC / rate;
if (period_ns <= MIN_PERIOD) {
dev_err(pc->dev, "period %d not supported, minimum %d\n",
@@ -73,8 +81,8 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
}
- writel(duty_ns / pc->scaler, pc->base + DUTY(pwm->hwpwm));
- writel(period_ns / pc->scaler, pc->base + PERIOD(pwm->hwpwm));
+ writel(duty_ns / scaler, pc->base + DUTY(pwm->hwpwm));
+ writel(period_ns / scaler, pc->base + PERIOD(pwm->hwpwm));
return 0;
}
@@ -156,8 +164,6 @@ static int bcm2835_pwm_probe(struct platform_device *pdev)
if (ret)
return ret;
- pc->scaler = NSEC_PER_SEC / clk_get_rate(pc->clk);
-
pc->chip.dev = &pdev->dev;
pc->chip.ops = &bcm2835_pwm_ops;
pc->chip.npwm = 2;
@@ -200,6 +206,6 @@ static struct platform_driver bcm2835_pwm_driver = {
};
module_platform_driver(bcm2835_pwm_driver);
-MODULE_AUTHOR("Bart Tanghe <bart.tanghe@thomasmore.be");
+MODULE_AUTHOR("Bart Tanghe <bart.tanghe@thomasmore.be>");
MODULE_DESCRIPTION("Broadcom BCM2835 PWM driver");
MODULE_LICENSE("GPL v2");
diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index f9dfc8b6407a..7225ac6b3df5 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -80,7 +80,6 @@ struct fsl_pwm_chip {
struct mutex lock;
- unsigned int use_count;
unsigned int cnt_select;
unsigned int clk_ps;
@@ -300,9 +299,6 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
{
int ret;
- if (fpc->use_count++ != 0)
- return 0;
-
/* select counter clock source */
regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK,
FTM_SC_CLK(fpc->cnt_select));
@@ -334,25 +330,6 @@ static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
return ret;
}
-static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)
-{
- /*
- * already disabled, do nothing
- */
- if (fpc->use_count == 0)
- return;
-
- /* there are still users, so can't disable yet */
- if (--fpc->use_count > 0)
- return;
-
- /* no users left, disable PWM counter clock */
- regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK, 0);
-
- clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
- clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
-}
-
static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
@@ -362,7 +339,8 @@ static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm),
BIT(pwm->hwpwm));
- fsl_counter_clock_disable(fpc);
+ clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
+ clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
regmap_read(fpc->regmap, FTM_OUTMASK, &val);
if ((val & 0xFF) == 0xFF)
@@ -492,17 +470,24 @@ static int fsl_pwm_remove(struct platform_device *pdev)
static int fsl_pwm_suspend(struct device *dev)
{
struct fsl_pwm_chip *fpc = dev_get_drvdata(dev);
- u32 val;
+ int i;
regcache_cache_only(fpc->regmap, true);
regcache_mark_dirty(fpc->regmap);
- /* read from cache */
- regmap_read(fpc->regmap, FTM_OUTMASK, &val);
- if ((val & 0xFF) != 0xFF) {
+ for (i = 0; i < fpc->chip.npwm; i++) {
+ struct pwm_device *pwm = &fpc->chip.pwms[i];
+
+ if (!test_bit(PWMF_REQUESTED, &pwm->flags))
+ continue;
+
+ clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
+
+ if (!pwm_is_enabled(pwm))
+ continue;
+
clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
- clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
}
return 0;
@@ -511,12 +496,19 @@ static int fsl_pwm_suspend(struct device *dev)
static int fsl_pwm_resume(struct device *dev)
{
struct fsl_pwm_chip *fpc = dev_get_drvdata(dev);
- u32 val;
+ int i;
+
+ for (i = 0; i < fpc->chip.npwm; i++) {
+ struct pwm_device *pwm = &fpc->chip.pwms[i];
+
+ if (!test_bit(PWMF_REQUESTED, &pwm->flags))
+ continue;
- /* read from cache */
- regmap_read(fpc->regmap, FTM_OUTMASK, &val);
- if ((val & 0xFF) != 0xFF) {
clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]);
+
+ if (!pwm_is_enabled(pwm))
+ continue;
+
clk_prepare_enable(fpc->clk[fpc->cnt_select]);
clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
}
diff --git a/drivers/pwm/pwm-lpc32xx.c b/drivers/pwm/pwm-lpc32xx.c
index 9fde60ce8e7b..4d470c1a406a 100644
--- a/drivers/pwm/pwm-lpc32xx.c
+++ b/drivers/pwm/pwm-lpc32xx.c
@@ -24,9 +24,7 @@ struct lpc32xx_pwm_chip {
void __iomem *base;
};
-#define PWM_ENABLE (1 << 31)
-#define PWM_RELOADV(x) (((x) & 0xFF) << 8)
-#define PWM_DUTY(x) ((x) & 0xFF)
+#define PWM_ENABLE BIT(31)
#define to_lpc32xx_pwm_chip(_chip) \
container_of(_chip, struct lpc32xx_pwm_chip, chip)
@@ -38,40 +36,27 @@ static int lpc32xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long long c;
int period_cycles, duty_cycles;
u32 val;
-
- c = clk_get_rate(lpc32xx->clk) / 256;
- c = c * period_ns;
- do_div(c, NSEC_PER_SEC);
-
- /* Handle high and low extremes */
- if (c == 0)
- c = 1;
- if (c > 255)
- c = 0; /* 0 set division by 256 */
- period_cycles = c;
-
- /* The duty-cycle value is as follows:
- *
- * DUTY-CYCLE HIGH LEVEL
- * 1 99.9%
- * 25 90.0%
- * 128 50.0%
- * 220 10.0%
- * 255 0.1%
- * 0 0.0%
- *
- * In other words, the register value is duty-cycle % 256 with
- * duty-cycle in the range 1-256.
- */
- c = 256 * duty_ns;
- do_div(c, period_ns);
- if (c > 255)
- c = 255;
- duty_cycles = 256 - c;
+ c = clk_get_rate(lpc32xx->clk);
+
+ /* The highest acceptable divisor is 256, which is represented by 0 */
+ period_cycles = div64_u64(c * period_ns,
+ (unsigned long long)NSEC_PER_SEC * 256);
+ if (!period_cycles || period_cycles > 256)
+ return -ERANGE;
+ if (period_cycles == 256)
+ period_cycles = 0;
+
+ /* Compute 256 x #duty/period value and care for corner cases */
+ duty_cycles = div64_u64((unsigned long long)(period_ns - duty_ns) * 256,
+ period_ns);
+ if (!duty_cycles)
+ duty_cycles = 1;
+ if (duty_cycles > 255)
+ duty_cycles = 255;
val = readl(lpc32xx->base + (pwm->hwpwm << 2));
val &= ~0xFFFF;
- val |= PWM_RELOADV(period_cycles) | PWM_DUTY(duty_cycles);
+ val |= (period_cycles << 8) | duty_cycles;
writel(val, lpc32xx->base + (pwm->hwpwm << 2));
return 0;
@@ -83,7 +68,7 @@ static int lpc32xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
u32 val;
int ret;
- ret = clk_enable(lpc32xx->clk);
+ ret = clk_prepare_enable(lpc32xx->clk);
if (ret)
return ret;
@@ -103,7 +88,7 @@ static void lpc32xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
val &= ~PWM_ENABLE;
writel(val, lpc32xx->base + (pwm->hwpwm << 2));
- clk_disable(lpc32xx->clk);
+ clk_disable_unprepare(lpc32xx->clk);
}
static const struct pwm_ops lpc32xx_pwm_ops = {
@@ -134,7 +119,7 @@ static int lpc32xx_pwm_probe(struct platform_device *pdev)
lpc32xx->chip.dev = &pdev->dev;
lpc32xx->chip.ops = &lpc32xx_pwm_ops;
- lpc32xx->chip.npwm = 2;
+ lpc32xx->chip.npwm = 1;
lpc32xx->chip.base = -1;
ret = pwmchip_add(&lpc32xx->chip);
diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c
index 25044104003b..295b963dbddb 100644
--- a/drivers/pwm/pwm-lpss.c
+++ b/drivers/pwm/pwm-lpss.c
@@ -13,10 +13,12 @@
* published by the Free Software Foundation.
*/
+#include <linux/delay.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
+#include <linux/time.h>
#include "pwm-lpss.h"
@@ -24,11 +26,8 @@
#define PWM_ENABLE BIT(31)
#define PWM_SW_UPDATE BIT(30)
#define PWM_BASE_UNIT_SHIFT 8
-#define PWM_BASE_UNIT_MASK 0x00ffff00
#define PWM_ON_TIME_DIV_MASK 0x000000ff
#define PWM_DIVISION_CORRECTION 0x2
-#define PWM_LIMIT (0x8000 + PWM_DIVISION_CORRECTION)
-#define NSECS_PER_SEC 1000000000UL
/* Size of each PWM register space if multiple */
#define PWM_SIZE 0x400
@@ -36,13 +35,14 @@
struct pwm_lpss_chip {
struct pwm_chip chip;
void __iomem *regs;
- unsigned long clk_rate;
+ const struct pwm_lpss_boardinfo *info;
};
/* BayTrail */
const struct pwm_lpss_boardinfo pwm_lpss_byt_info = {
.clk_rate = 25000000,
.npwm = 1,
+ .base_unit_bits = 16,
};
EXPORT_SYMBOL_GPL(pwm_lpss_byt_info);
@@ -50,6 +50,7 @@ EXPORT_SYMBOL_GPL(pwm_lpss_byt_info);
const struct pwm_lpss_boardinfo pwm_lpss_bsw_info = {
.clk_rate = 19200000,
.npwm = 1,
+ .base_unit_bits = 16,
};
EXPORT_SYMBOL_GPL(pwm_lpss_bsw_info);
@@ -57,6 +58,7 @@ EXPORT_SYMBOL_GPL(pwm_lpss_bsw_info);
const struct pwm_lpss_boardinfo pwm_lpss_bxt_info = {
.clk_rate = 19200000,
.npwm = 4,
+ .base_unit_bits = 22,
};
EXPORT_SYMBOL_GPL(pwm_lpss_bxt_info);
@@ -79,28 +81,37 @@ static inline void pwm_lpss_write(const struct pwm_device *pwm, u32 value)
writel(value, lpwm->regs + pwm->hwpwm * PWM_SIZE + PWM);
}
+static void pwm_lpss_update(struct pwm_device *pwm)
+{
+ pwm_lpss_write(pwm, pwm_lpss_read(pwm) | PWM_SW_UPDATE);
+ /* Give it some time to propagate */
+ usleep_range(10, 50);
+}
+
static int pwm_lpss_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct pwm_lpss_chip *lpwm = to_lpwm(chip);
u8 on_time_div;
- unsigned long c;
- unsigned long long base_unit, freq = NSECS_PER_SEC;
+ unsigned long c, base_unit_range;
+ unsigned long long base_unit, freq = NSEC_PER_SEC;
u32 ctrl;
do_div(freq, period_ns);
- /* The equation is: base_unit = ((freq / c) * 65536) + correction */
- base_unit = freq * 65536;
+ /*
+ * The equation is:
+ * base_unit = ((freq / c) * base_unit_range) + correction
+ */
+ base_unit_range = BIT(lpwm->info->base_unit_bits);
+ base_unit = freq * base_unit_range;
- c = lpwm->clk_rate;
+ c = lpwm->info->clk_rate;
if (!c)
return -EINVAL;
do_div(base_unit, c);
base_unit += PWM_DIVISION_CORRECTION;
- if (base_unit > PWM_LIMIT)
- return -EINVAL;
if (duty_ns <= 0)
duty_ns = 1;
@@ -109,13 +120,20 @@ static int pwm_lpss_config(struct pwm_chip *chip, struct pwm_device *pwm,
pm_runtime_get_sync(chip->dev);
ctrl = pwm_lpss_read(pwm);
- ctrl &= ~(PWM_BASE_UNIT_MASK | PWM_ON_TIME_DIV_MASK);
- ctrl |= (u16) base_unit << PWM_BASE_UNIT_SHIFT;
+ ctrl &= ~PWM_ON_TIME_DIV_MASK;
+ ctrl &= ~((base_unit_range - 1) << PWM_BASE_UNIT_SHIFT);
+ base_unit &= (base_unit_range - 1);
+ ctrl |= (u32) base_unit << PWM_BASE_UNIT_SHIFT;
ctrl |= on_time_div;
- /* request PWM to update on next cycle */
- ctrl |= PWM_SW_UPDATE;
pwm_lpss_write(pwm, ctrl);
+ /*
+ * If the PWM is already enabled we need to notify the hardware
+ * about the change by setting PWM_SW_UPDATE.
+ */
+ if (pwm_is_enabled(pwm))
+ pwm_lpss_update(pwm);
+
pm_runtime_put(chip->dev);
return 0;
@@ -124,6 +142,12 @@ static int pwm_lpss_config(struct pwm_chip *chip, struct pwm_device *pwm,
static int pwm_lpss_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
pm_runtime_get_sync(chip->dev);
+
+ /*
+ * Hardware must first see PWM_SW_UPDATE before the PWM can be
+ * enabled.
+ */
+ pwm_lpss_update(pwm);
pwm_lpss_write(pwm, pwm_lpss_read(pwm) | PWM_ENABLE);
return 0;
}
@@ -135,7 +159,6 @@ static void pwm_lpss_disable(struct pwm_chip *chip, struct pwm_device *pwm)
}
static const struct pwm_ops pwm_lpss_ops = {
- .free = pwm_lpss_disable,
.config = pwm_lpss_config,
.enable = pwm_lpss_enable,
.disable = pwm_lpss_disable,
@@ -156,7 +179,7 @@ struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev, struct resource *r,
if (IS_ERR(lpwm->regs))
return ERR_CAST(lpwm->regs);
- lpwm->clk_rate = info->clk_rate;
+ lpwm->info = info;
lpwm->chip.dev = dev;
lpwm->chip.ops = &pwm_lpss_ops;
lpwm->chip.base = -1;
diff --git a/drivers/pwm/pwm-lpss.h b/drivers/pwm/pwm-lpss.h
index e8cf337ae1d1..04766e0d41aa 100644
--- a/drivers/pwm/pwm-lpss.h
+++ b/drivers/pwm/pwm-lpss.h
@@ -21,6 +21,7 @@ struct pwm_lpss_chip;
struct pwm_lpss_boardinfo {
unsigned long clk_rate;
unsigned int npwm;
+ unsigned long base_unit_bits;
};
extern const struct pwm_lpss_boardinfo pwm_lpss_byt_info;
diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c
new file mode 100644
index 000000000000..826634ec0d5c
--- /dev/null
+++ b/drivers/pwm/pwm-omap-dmtimer.c
@@ -0,0 +1,327 @@
+/*
+ * Copyright (c) 2015 Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (c) 2014 Joachim Eastwood <manabian@gmail.com>
+ * Copyright (c) 2012 NeilBrown <neilb@suse.de>
+ * Heavily based on earlier code which is:
+ * Copyright (c) 2010 Grant Erickson <marathon96@gmail.com>
+ *
+ * Also based on pwm-samsung.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * Description:
+ * This file is the core OMAP support for the generic, Linux
+ * PWM driver / controller, using the OMAP's dual-mode timers.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_data/pwm_omap_dmtimer.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+
+#define DM_TIMER_LOAD_MIN 0xfffffffe
+
+struct pwm_omap_dmtimer_chip {
+ struct pwm_chip chip;
+ struct mutex mutex;
+ pwm_omap_dmtimer *dm_timer;
+ struct pwm_omap_dmtimer_pdata *pdata;
+ struct platform_device *dm_timer_pdev;
+};
+
+static inline struct pwm_omap_dmtimer_chip *
+to_pwm_omap_dmtimer_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct pwm_omap_dmtimer_chip, chip);
+}
+
+static int pwm_omap_dmtimer_calc_value(unsigned long clk_rate, int ns)
+{
+ u64 c = (u64)clk_rate * ns;
+
+ do_div(c, NSEC_PER_SEC);
+
+ return DM_TIMER_LOAD_MIN - c;
+}
+
+static void pwm_omap_dmtimer_start(struct pwm_omap_dmtimer_chip *omap)
+{
+ /*
+ * According to OMAP 4 TRM section 22.2.4.10 the counter should be
+ * started at 0xFFFFFFFE when overflow and match is used to ensure
+ * that the PWM line is toggled on the first event.
+ *
+ * Note that omap_dm_timer_enable/disable is for register access and
+ * not the timer counter itself.
+ */
+ omap->pdata->enable(omap->dm_timer);
+ omap->pdata->write_counter(omap->dm_timer, DM_TIMER_LOAD_MIN);
+ omap->pdata->disable(omap->dm_timer);
+
+ omap->pdata->start(omap->dm_timer);
+}
+
+static int pwm_omap_dmtimer_enable(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);
+
+ mutex_lock(&omap->mutex);
+ pwm_omap_dmtimer_start(omap);
+ mutex_unlock(&omap->mutex);
+
+ return 0;
+}
+
+static void pwm_omap_dmtimer_disable(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);
+
+ mutex_lock(&omap->mutex);
+ omap->pdata->stop(omap->dm_timer);
+ mutex_unlock(&omap->mutex);
+}
+
+static int pwm_omap_dmtimer_config(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);
+ int load_value, match_value;
+ struct clk *fclk;
+ unsigned long clk_rate;
+ bool timer_active;
+
+ dev_dbg(chip->dev, "duty cycle: %d, period %d\n", duty_ns, period_ns);
+
+ mutex_lock(&omap->mutex);
+ if (duty_ns == pwm_get_duty_cycle(pwm) &&
+ period_ns == pwm_get_period(pwm)) {
+ /* No change - don't cause any transients. */
+ mutex_unlock(&omap->mutex);
+ return 0;
+ }
+
+ fclk = omap->pdata->get_fclk(omap->dm_timer);
+ if (!fclk) {
+ dev_err(chip->dev, "invalid pmtimer fclk\n");
+ mutex_unlock(&omap->mutex);
+ return -EINVAL;
+ }
+
+ clk_rate = clk_get_rate(fclk);
+ if (!clk_rate) {
+ dev_err(chip->dev, "invalid pmtimer fclk rate\n");
+ mutex_unlock(&omap->mutex);
+ return -EINVAL;
+ }
+
+ dev_dbg(chip->dev, "clk rate: %luHz\n", clk_rate);
+
+ /*
+ * Calculate the appropriate load and match values based on the
+ * specified period and duty cycle. The load value determines the
+ * cycle time and the match value determines the duty cycle.
+ */
+ load_value = pwm_omap_dmtimer_calc_value(clk_rate, period_ns);
+ match_value = pwm_omap_dmtimer_calc_value(clk_rate,
+ period_ns - duty_ns);
+
+ /*
+ * We MUST stop the associated dual-mode timer before attempting to
+ * write its registers, but calls to omap_dm_timer_start/stop must
+ * be balanced so check if timer is active before calling timer_stop.
+ */
+ timer_active = pm_runtime_active(&omap->dm_timer_pdev->dev);
+ if (timer_active)
+ omap->pdata->stop(omap->dm_timer);
+
+ omap->pdata->set_load(omap->dm_timer, true, load_value);
+ omap->pdata->set_match(omap->dm_timer, true, match_value);
+
+ dev_dbg(chip->dev, "load value: %#08x (%d), match value: %#08x (%d)\n",
+ load_value, load_value, match_value, match_value);
+
+ omap->pdata->set_pwm(omap->dm_timer,
+ pwm->polarity == PWM_POLARITY_INVERSED,
+ true,
+ PWM_OMAP_DMTIMER_TRIGGER_OVERFLOW_AND_COMPARE);
+
+ /* If config was called while timer was running it must be reenabled. */
+ if (timer_active)
+ pwm_omap_dmtimer_start(omap);
+
+ mutex_unlock(&omap->mutex);
+
+ return 0;
+}
+
+static int pwm_omap_dmtimer_set_polarity(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ enum pwm_polarity polarity)
+{
+ struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);
+
+ /*
+ * PWM core will not call set_polarity while PWM is enabled so it's
+ * safe to reconfigure the timer here without stopping it first.
+ */
+ mutex_lock(&omap->mutex);
+ omap->pdata->set_pwm(omap->dm_timer,
+ polarity == PWM_POLARITY_INVERSED,
+ true,
+ PWM_OMAP_DMTIMER_TRIGGER_OVERFLOW_AND_COMPARE);
+ mutex_unlock(&omap->mutex);
+
+ return 0;
+}
+
+static const struct pwm_ops pwm_omap_dmtimer_ops = {
+ .enable = pwm_omap_dmtimer_enable,
+ .disable = pwm_omap_dmtimer_disable,
+ .config = pwm_omap_dmtimer_config,
+ .set_polarity = pwm_omap_dmtimer_set_polarity,
+ .owner = THIS_MODULE,
+};
+
+static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *timer;
+ struct pwm_omap_dmtimer_chip *omap;
+ struct pwm_omap_dmtimer_pdata *pdata;
+ pwm_omap_dmtimer *dm_timer;
+ u32 prescaler;
+ int status;
+
+ pdata = dev_get_platdata(&pdev->dev);
+ if (!pdata) {
+ dev_err(&pdev->dev, "Missing dmtimer platform data\n");
+ return -EINVAL;
+ }
+
+ if (!pdata->request_by_node ||
+ !pdata->free ||
+ !pdata->enable ||
+ !pdata->disable ||
+ !pdata->get_fclk ||
+ !pdata->start ||
+ !pdata->stop ||
+ !pdata->set_load ||
+ !pdata->set_match ||
+ !pdata->set_pwm ||
+ !pdata->set_prescaler ||
+ !pdata->write_counter) {
+ dev_err(&pdev->dev, "Incomplete dmtimer pdata structure\n");
+ return -EINVAL;
+ }
+
+ timer = of_parse_phandle(np, "ti,timers", 0);
+ if (!timer)
+ return -ENODEV;
+
+ if (!of_get_property(timer, "ti,timer-pwm", NULL)) {
+ dev_err(&pdev->dev, "Missing ti,timer-pwm capability\n");
+ return -ENODEV;
+ }
+
+ dm_timer = pdata->request_by_node(timer);
+ if (!dm_timer)
+ return -EPROBE_DEFER;
+
+ omap = devm_kzalloc(&pdev->dev, sizeof(*omap), GFP_KERNEL);
+ if (!omap) {
+ pdata->free(dm_timer);
+ return -ENOMEM;
+ }
+
+ omap->pdata = pdata;
+ omap->dm_timer = dm_timer;
+
+ omap->dm_timer_pdev = of_find_device_by_node(timer);
+ if (!omap->dm_timer_pdev) {
+ dev_err(&pdev->dev, "Unable to find timer pdev\n");
+ omap->pdata->free(dm_timer);
+ return -EINVAL;
+ }
+
+ /*
+ * Ensure that the timer is stopped before we allow PWM core to call
+ * pwm_enable.
+ */
+ if (pm_runtime_active(&omap->dm_timer_pdev->dev))
+ omap->pdata->stop(omap->dm_timer);
+
+ /* setup dmtimer prescaler */
+ if (!of_property_read_u32(pdev->dev.of_node, "ti,prescaler",
+ &prescaler))
+ omap->pdata->set_prescaler(omap->dm_timer, prescaler);
+
+ omap->chip.dev = &pdev->dev;
+ omap->chip.ops = &pwm_omap_dmtimer_ops;
+ omap->chip.base = -1;
+ omap->chip.npwm = 1;
+ omap->chip.of_xlate = of_pwm_xlate_with_flags;
+ omap->chip.of_pwm_n_cells = 3;
+
+ mutex_init(&omap->mutex);
+
+ status = pwmchip_add(&omap->chip);
+ if (status < 0) {
+ dev_err(&pdev->dev, "failed to register PWM\n");
+ omap->pdata->free(omap->dm_timer);
+ return status;
+ }
+
+ platform_set_drvdata(pdev, omap);
+
+ return 0;
+}
+
+static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
+{
+ struct pwm_omap_dmtimer_chip *omap = platform_get_drvdata(pdev);
+
+ if (pm_runtime_active(&omap->dm_timer_pdev->dev))
+ omap->pdata->stop(omap->dm_timer);
+
+ omap->pdata->free(omap->dm_timer);
+
+ mutex_destroy(&omap->mutex);
+
+ return pwmchip_remove(&omap->chip);
+}
+
+static const struct of_device_id pwm_omap_dmtimer_of_match[] = {
+ {.compatible = "ti,omap-dmtimer-pwm"},
+ {}
+};
+MODULE_DEVICE_TABLE(of, pwm_omap_dmtimer_of_match);
+
+static struct platform_driver pwm_omap_dmtimer_driver = {
+ .driver = {
+ .name = "omap-dmtimer-pwm",
+ .of_match_table = of_match_ptr(pwm_omap_dmtimer_of_match),
+ },
+ .probe = pwm_omap_dmtimer_probe,
+ .remove = pwm_omap_dmtimer_remove,
+};
+module_platform_driver(pwm_omap_dmtimer_driver);
+
+MODULE_AUTHOR("Grant Erickson <marathon96@gmail.com>");
+MODULE_AUTHOR("NeilBrown <neilb@suse.de>");
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("OMAP PWM Driver using Dual-mode Timers");
diff --git a/drivers/pwm/pwm-rcar.c b/drivers/pwm/pwm-rcar.c
index 6e99a63ffa29..7b8ac0678137 100644
--- a/drivers/pwm/pwm-rcar.c
+++ b/drivers/pwm/pwm-rcar.c
@@ -81,7 +81,7 @@ static int rcar_pwm_get_clock_division(struct rcar_pwm_chip *rp, int period_ns)
max = (unsigned long long)NSEC_PER_SEC * RCAR_PWM_MAX_CYCLE *
(1 << div);
do_div(max, clk_rate);
- if (period_ns < max)
+ if (period_ns <= max)
break;
}
diff --git a/include/linux/platform_data/pwm_omap_dmtimer.h b/include/linux/platform_data/pwm_omap_dmtimer.h
new file mode 100644
index 000000000000..59384217208f
--- /dev/null
+++ b/include/linux/platform_data/pwm_omap_dmtimer.h
@@ -0,0 +1,69 @@
+/*
+ * include/linux/platform_data/pwm_omap_dmtimer.h
+ *
+ * OMAP Dual-Mode Timer PWM platform data
+ *
+ * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
+ * Tarun Kanti DebBarma <tarun.kanti@ti.com>
+ * Thara Gopinath <thara@ti.com>
+ *
+ * Platform device conversion and hwmod support.
+ *
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Lauri Leukkunen <lauri.leukkunen@nokia.com>
+ * PWM and clock framework support by Timo Teras.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __PWM_OMAP_DMTIMER_PDATA_H
+#define __PWM_OMAP_DMTIMER_PDATA_H
+
+/* trigger types */
+#define PWM_OMAP_DMTIMER_TRIGGER_NONE 0x00
+#define PWM_OMAP_DMTIMER_TRIGGER_OVERFLOW 0x01
+#define PWM_OMAP_DMTIMER_TRIGGER_OVERFLOW_AND_COMPARE 0x02
+
+struct omap_dm_timer;
+typedef struct omap_dm_timer pwm_omap_dmtimer;
+
+struct pwm_omap_dmtimer_pdata {
+ pwm_omap_dmtimer *(*request_by_node)(struct device_node *np);
+ int (*free)(pwm_omap_dmtimer *timer);
+
+ void (*enable)(pwm_omap_dmtimer *timer);
+ void (*disable)(pwm_omap_dmtimer *timer);
+
+ struct clk *(*get_fclk)(pwm_omap_dmtimer *timer);
+
+ int (*start)(pwm_omap_dmtimer *timer);
+ int (*stop)(pwm_omap_dmtimer *timer);
+
+ int (*set_load)(pwm_omap_dmtimer *timer, int autoreload,
+ unsigned int value);
+ int (*set_match)(pwm_omap_dmtimer *timer, int enable,
+ unsigned int match);
+ int (*set_pwm)(pwm_omap_dmtimer *timer, int def_on,
+ int toggle, int trigger);
+ int (*set_prescaler)(pwm_omap_dmtimer *timer, int prescaler);
+
+ int (*write_counter)(pwm_omap_dmtimer *timer, unsigned int value);
+};
+
+#endif /* __PWM_OMAP_DMTIMER_PDATA_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 11:26:59 +0000