[PATCH v4 04/14] mfd: Add Samsung PWM/timer master driver
Tomasz Figa
t.figa at samsung.com
Fri Apr 5 03:37:01 EST 2013
This patch adds master driver for PWM/timer block available on many
Samsung SoCs providing clocksource and PWM output capabilities.
Signed-off-by: Tomasz Figa <t.figa at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
.../devicetree/bindings/pwm/pwm-samsung.txt | 37 ++
drivers/clocksource/Kconfig | 1 +
drivers/mfd/Kconfig | 3 +
drivers/mfd/Makefile | 1 +
drivers/mfd/samsung-pwm.c | 439 +++++++++++++++++++++
drivers/pwm/Kconfig | 1 +
include/linux/mfd/samsung-pwm.h | 49 +++
include/linux/platform_data/samsung-pwm.h | 28 ++
8 files changed, 559 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pwm/pwm-samsung.txt
create mode 100644 drivers/mfd/samsung-pwm.c
create mode 100644 include/linux/mfd/samsung-pwm.h
create mode 100644 include/linux/platform_data/samsung-pwm.h
diff --git a/Documentation/devicetree/bindings/pwm/pwm-samsung.txt b/Documentation/devicetree/bindings/pwm/pwm-samsung.txt
new file mode 100644
index 0000000..8ed4c11
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-samsung.txt
@@ -0,0 +1,37 @@
+* Samsung PWM timers
+
+Samsung SoCs contain PWM timer blocks which can be used for system clock source
+and clock event timers, as well as to drive SoC outputs with PWM signal. Each
+PWM timer block provides 5 PWM channels (not all of them can drive physical
+outputs - see SoC and board manual).
+
+Be aware that this driver supports clock event only on CPU 0. It can
+provide SMP support together with ARM dummy_timer, but only in periodic tick
+mode.
+
+Required properties:
+- compatible : should be one of following:
+ samsung,s3c2410-pwm - for 16-bit timers present on S3C24xx SoCs
+ samsung,s3c6400-pwm - for 32-bit timers present on S3C64xx SoCs
+ samsung,s5p6440-pwm - for 32-bit timers present on S5P64x0 SoCs
+ samsung,s5pc100-pwm - for 32-bit timers present on S5PC100, S5PV210,
+ Exynos4210, Exynos4x12 and Exynos5250 SoCs
+- reg: base address and size of register area
+- interrupts: list of timer interrupts (one interrupt per timer, starting at
+ timer 0)
+- #pwm-cells: number of cells used for PWM specifier - must be 2
+
+Optional properties:
+- samsung,pwm-outputs: list of PWM channels used as PWM outputs on particular
+ platform - an array of up to 5 elements being indices of PWM channels
+ (from 0 to 4), the order does not matter.
+
+Example:
+ pwm at 7f006000 {
+ compatible = "samsung,s3c6400-pwm";
+ reg = <0x7f006000 0x1000>;
+ interrupt-parent = <&vic0>;
+ interrupts = <23>, <24>, <25>, <27>, <28>;
+ samsung,pwm-outputs = <0>, <1>;
+ #pwm-cells = <2>;
+ }
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index dd20f6a..a69a5b7 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -29,6 +29,7 @@ config SAMSUNG_HRT
bool
depends on PLAT_SAMSUNG
select SAMSUNG_DEV_PWM
+ select MFD_SAMSUNG_PWM
help
Use the high resolution timer support on Samsung platforms.
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 3ab3a11..c25425c 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1015,6 +1015,9 @@ config MFD_PM8XXX_IRQ
This is required to use certain other PM 8xxx features, such as GPIO
and MPP.
+config MFD_SAMSUNG_PWM
+ bool
+
config TPS65911_COMPARATOR
tristate
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index b90409c..513d9c9 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -145,6 +145,7 @@ obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o
obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o
obj-$(CONFIG_MFD_SYSCON) += syscon.o
obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o
+obj-$(CONFIG_MFD_SAMSUNG_PWM) += samsung-pwm.o
obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o vexpress-sysreg.o
obj-$(CONFIG_MFD_RETU) += retu-mfd.o
obj-$(CONFIG_MFD_AS3711) += as3711.o
diff --git a/drivers/mfd/samsung-pwm.c b/drivers/mfd/samsung-pwm.c
new file mode 100644
index 0000000..ece426e
--- /dev/null
+++ b/drivers/mfd/samsung-pwm.c
@@ -0,0 +1,439 @@
+/*
+ * Samsung PWM/timers MFD driver
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Tomasz Figa <t.figa at samsung.com>
+ *
+ * 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.
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/mfd/samsung-pwm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_data/samsung-pwm.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#define REG_TCFG0 0x00
+#define REG_TCFG1 0x04
+#define REG_TCON 0x08
+
+#define REG_TCNTB(chan) (0x0c + 12 * (chan))
+#define REG_TCMPB(chan) (0x10 + 12 * (chan))
+
+#define TCON_START(chan) (1 << (4 * (chan) + 0))
+#define TCON_MANUALUPDATE(chan) (1 << (4 * (chan) + 1))
+#define TCON_INVERT(chan) (1 << (4 * (chan) + 2))
+#define TCON_AUTORELOAD(chan) (1 << (4 * (chan) + 3))
+
+#define TCFG0_PRESCALER_MASK 0xff
+#define TCFG0_PRESCALER1_SHIFT 8
+
+#define TCFG1_SHIFT(x) ((x) * 4)
+#define TCFG1_MUX_MASK 0xf
+
+struct samsung_pwm_drvdata {
+ struct samsung_pwm pwm;
+ struct platform_device *pdev;
+ struct resource resource;
+ struct list_head list;
+ spinlock_t slock;
+ unsigned long request_mask;
+};
+
+static LIST_HEAD(pwm_list);
+
+static inline struct samsung_pwm_drvdata *to_drvdata(struct samsung_pwm *pwm)
+{
+ return container_of(pwm, struct samsung_pwm_drvdata, pwm);
+}
+
+void samsung_pwm_start(struct samsung_pwm *pwm,
+ unsigned int channel, bool periodic)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+ unsigned long flags;
+ u32 reg;
+
+ if (channel > 0)
+ ++channel;
+
+ spin_lock_irqsave(&drvdata->slock, flags);
+
+ reg = readl(pwm->base + REG_TCON);
+ reg &= ~TCON_MANUALUPDATE(channel);
+ reg |= TCON_START(channel);
+ if (periodic)
+ reg |= TCON_AUTORELOAD(channel);
+ else
+ reg &= ~TCON_AUTORELOAD(channel);
+ writel(reg, pwm->base + REG_TCON);
+
+ spin_unlock_irqrestore(&drvdata->slock, flags);
+}
+EXPORT_SYMBOL(samsung_pwm_start);
+
+void samsung_pwm_stop(struct samsung_pwm *pwm, unsigned int channel)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+ unsigned long flags;
+ u32 reg;
+
+ if (channel > 0)
+ ++channel;
+
+ spin_lock_irqsave(&drvdata->slock, flags);
+
+ reg = readl(pwm->base + REG_TCON);
+ reg &= ~TCON_START(channel);
+ writel(reg, pwm->base + REG_TCON);
+
+ spin_unlock_irqrestore(&drvdata->slock, flags);
+}
+EXPORT_SYMBOL(samsung_pwm_stop);
+
+void samsung_pwm_setup(struct samsung_pwm *pwm, unsigned int channel,
+ u32 tcmp, u32 tcnt)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+ unsigned long flags;
+ u32 reg;
+
+ writel(tcnt, pwm->base + REG_TCNTB(channel));
+ writel(tcmp, pwm->base + REG_TCMPB(channel));
+
+ if (channel > 0)
+ ++channel;
+
+ spin_lock_irqsave(&drvdata->slock, flags);
+
+ reg = readl(pwm->base + REG_TCON);
+ reg &= ~TCON_START(channel);
+ reg |= TCON_MANUALUPDATE(channel);
+ writel(reg, pwm->base + REG_TCON);
+
+ spin_unlock_irqrestore(&drvdata->slock, flags);
+}
+EXPORT_SYMBOL(samsung_pwm_setup);
+
+void samsung_pwm_set_flags(struct samsung_pwm *pwm,
+ unsigned int channel, u32 pwm_flags)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+ unsigned long flags;
+ u32 reg;
+
+ if (channel > 0)
+ ++channel;
+
+ spin_lock_irqsave(&drvdata->slock, flags);
+
+ reg = readl(pwm->base + REG_TCON);
+
+ if (pwm_flags & SAMSUNG_PWM_INVERT)
+ reg |= TCON_INVERT(channel);
+ else
+ reg &= ~TCON_INVERT(channel);
+
+ writel(reg, pwm->base + REG_TCON);
+
+ spin_unlock_irqrestore(&drvdata->slock, flags);
+}
+EXPORT_SYMBOL(samsung_pwm_set_flags);
+
+void samsung_pwm_set_prescale(struct samsung_pwm *pwm,
+ unsigned int channel, u16 prescale)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+ unsigned long flags;
+ u8 shift = 0;
+ u32 reg;
+
+ if (channel >= 2)
+ shift = TCFG0_PRESCALER1_SHIFT;
+
+ spin_lock_irqsave(&drvdata->slock, flags);
+
+ reg = readl(pwm->base + REG_TCFG0);
+ reg &= ~(TCFG0_PRESCALER_MASK << shift);
+ reg |= (prescale - 1) << shift;
+ writel(reg, pwm->base + REG_TCFG0);
+
+ spin_unlock_irqrestore(&drvdata->slock, flags);
+}
+EXPORT_SYMBOL(samsung_pwm_set_prescale);
+
+void samsung_pwm_set_divisor(struct samsung_pwm *pwm,
+ unsigned int channel, u8 divisor)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+ u8 shift = TCFG1_SHIFT(channel);
+ unsigned long flags;
+ u32 reg;
+ u8 bits;
+
+ bits = (fls(divisor) - 1) - pwm->variant.div_base;
+
+ spin_lock_irqsave(&drvdata->slock, flags);
+
+ reg = readl(pwm->base + REG_TCFG1);
+ reg &= ~(TCFG1_MUX_MASK << shift);
+ reg |= bits << shift;
+ writel(reg, pwm->base + REG_TCFG1);
+
+ spin_unlock_irqrestore(&drvdata->slock, flags);
+}
+EXPORT_SYMBOL(samsung_pwm_set_divisor);
+
+int samsung_pwm_request(struct samsung_pwm *pwm, unsigned int channel)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+
+ if (test_and_set_bit(channel, &drvdata->request_mask))
+ return -EBUSY;
+
+ return 0;
+}
+EXPORT_SYMBOL(samsung_pwm_request);
+
+void samsung_pwm_free(struct samsung_pwm *pwm, unsigned int channel)
+{
+ struct samsung_pwm_drvdata *drvdata = to_drvdata(pwm);
+
+ clear_bit(channel, &drvdata->request_mask);
+}
+EXPORT_SYMBOL(samsung_pwm_free);
+
+#ifdef CONFIG_OF
+static int samsung_pwm_parse_dt(struct samsung_pwm *pwm)
+{
+ struct samsung_pwm_variant *variant = &pwm->variant;
+ struct device_node *np = pwm->of_node;
+ struct property *prop;
+ const __be32 *cur;
+ u32 val;
+ int i;
+
+ for (i = 0; i < SAMSUNG_PWM_NUM; ++i)
+ pwm->irq[i] = irq_of_parse_and_map(np, i);
+
+ of_property_for_each_u32(np, "samsung,pwm-outputs", prop, cur, val) {
+ if (val >= SAMSUNG_PWM_NUM) {
+ pr_warning("%s: invalid channel index in samsung,pwm-outputs property\n",
+ __func__);
+ continue;
+ }
+ variant->output_mask |= 1 << val;
+ }
+
+ return 0;
+}
+
+static const struct samsung_pwm_variant s3c24xx_variant = {
+ .bits = 16,
+ .div_base = 1,
+ .has_tint_cstat = false,
+ .tclk_mask = (1 << 4),
+};
+
+static const struct samsung_pwm_variant s3c64xx_variant = {
+ .bits = 32,
+ .div_base = 0,
+ .has_tint_cstat = true,
+ .tclk_mask = (1 << 7) | (1 << 6) | (1 << 5),
+};
+
+static const struct samsung_pwm_variant s5p64x0_variant = {
+ .bits = 32,
+ .div_base = 0,
+ .has_tint_cstat = true,
+ .tclk_mask = 0,
+};
+
+static const struct samsung_pwm_variant s5p_variant = {
+ .bits = 32,
+ .div_base = 0,
+ .has_tint_cstat = true,
+ .tclk_mask = (1 << 5),
+};
+
+static const struct of_device_id samsung_pwm_matches[] = {
+ { .compatible = "samsung,s3c2410-pwm", .data = &s3c24xx_variant, },
+ { .compatible = "samsung,s3c6400-pwm", .data = &s3c64xx_variant, },
+ { .compatible = "samsung,s5p6440-pwm", .data = &s5p64x0_variant, },
+ { .compatible = "samsung,s5pc100-pwm", .data = &s5p_variant, },
+ {},
+};
+
+static struct samsung_pwm_drvdata *samsung_pwm_of_add(struct device_node *np)
+{
+ const struct samsung_pwm_variant *variant;
+ const struct of_device_id *match;
+ struct samsung_pwm_drvdata *pwm;
+ int ret;
+
+ if (!np) {
+ np = of_find_matching_node(NULL, samsung_pwm_matches);
+ if (!np) {
+ pr_err("%s: could not find PWM device\n", __func__);
+ return ERR_PTR(-ENODEV);
+ }
+ }
+
+ match = of_match_node(samsung_pwm_matches, np);
+ if (!match) {
+ pr_err("%s: failed to match given OF node\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+ variant = match->data;
+
+ pwm = kzalloc(sizeof(*pwm), GFP_KERNEL);
+ if (!pwm) {
+ pr_err("%s: could not allocate PWM device struct\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pwm->pwm.variant = *variant;
+ pwm->pwm.of_node = np;
+ spin_lock_init(&pwm->slock);
+
+ ret = of_address_to_resource(np, 0, &pwm->resource);
+ if (ret < 0) {
+ pr_err("%s: could not get IO resource\n", __func__);
+ goto err_free;
+ }
+
+ ret = samsung_pwm_parse_dt(&pwm->pwm);
+ if (ret < 0) {
+ pr_err("%s: failed to parse device tree node\n", __func__);
+ goto err_free;
+ }
+
+ list_add_tail(&pwm->list, &pwm_list);
+
+ return pwm;
+
+err_free:
+ kfree(pwm);
+
+ return ERR_PTR(ret);
+}
+#else
+static struct samsung_pwm_drvdata *samsung_pwm_of_add(struct device_node *np)
+{
+ return ERR_PTR(-ENODEV);
+}
+#endif
+
+static struct samsung_pwm_drvdata *samsung_pwm_add(struct platform_device *pdev)
+{
+ struct samsung_pwm_variant *variant = pdev->dev.platform_data;
+ struct samsung_pwm_drvdata *pwm;
+ struct resource *res;
+ int i;
+
+ if (!variant) {
+ pr_err("%s: no platform data specified\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+
+ pwm = kzalloc(sizeof(*pwm), GFP_KERNEL);
+ if (!pwm) {
+ pr_err("%s: could not allocate PWM device struct\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pwm->pwm.variant = *variant;
+ pwm->pdev = pdev;
+ spin_lock_init(&pwm->slock);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ pr_err("%s: could not get IO resource\n", __func__);
+ kfree(pwm);
+ return ERR_PTR(-EINVAL);
+ }
+ pwm->resource = *res;
+
+ for (i = 0; i < SAMSUNG_PWM_NUM; ++i)
+ pwm->pwm.irq[i] = platform_get_irq(pdev, i);
+
+ list_add_tail(&pwm->list, &pwm_list);
+
+ return pwm;
+}
+
+static struct samsung_pwm_drvdata *samsung_pwm_find(struct platform_device *pdev)
+{
+ struct samsung_pwm_drvdata *pwm;
+ struct device_node *np = NULL;
+
+ list_for_each_entry(pwm, &pwm_list, list) {
+ if (!pdev || pwm->pdev == pdev)
+ return pwm;
+ if (pdev->dev.of_node && pdev->dev.of_node == pwm->pwm.of_node)
+ return pwm;
+ }
+
+ if (pdev) {
+ np = pdev->dev.of_node;
+ if (!np)
+ return samsung_pwm_add(pdev);
+ }
+
+ return samsung_pwm_of_add(np);
+}
+
+struct samsung_pwm *samsung_pwm_get(struct platform_device *pdev)
+{
+ struct samsung_pwm_drvdata *pwm;
+ struct resource *res;
+
+ pwm = samsung_pwm_find(pdev);
+ if (IS_ERR(pwm)) {
+ pr_err("%s: failed to instantiate PWM device\n", __func__);
+ return &pwm->pwm;
+ }
+
+ if (pwm->pwm.base)
+ return &pwm->pwm;
+
+ res = request_mem_region(pwm->resource.start,
+ resource_size(&pwm->resource), "samsung-pwm");
+ if (!res) {
+ pr_err("%s: failed to request IO mem region\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pwm->pwm.base = ioremap(res->start, resource_size(res));
+ if (!pwm->pwm.base) {
+ pr_err("%s: failed to map PWM registers\n", __func__);
+ release_mem_region(res->start, resource_size(res));
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return &pwm->pwm;
+}
+EXPORT_SYMBOL(samsung_pwm_get);
+
+int samsung_pwm_register(struct platform_device *pdev)
+{
+ struct samsung_pwm_drvdata *pwm;
+
+ pwm = samsung_pwm_add(pdev);
+ if (IS_ERR(pwm))
+ return PTR_ERR(pwm);
+
+ return 0;
+}
+EXPORT_SYMBOL(samsung_pwm_register);
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 0e0bfa0..c80070b 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -118,6 +118,7 @@ config PWM_PXA
config PWM_SAMSUNG
tristate "Samsung PWM support"
depends on PLAT_SAMSUNG
+ select MFD_SAMSUNG_PWM
help
Generic PWM framework driver for Samsung.
diff --git a/include/linux/mfd/samsung-pwm.h b/include/linux/mfd/samsung-pwm.h
new file mode 100644
index 0000000..e54456e
--- /dev/null
+++ b/include/linux/mfd/samsung-pwm.h
@@ -0,0 +1,49 @@
+/*
+ * Samsung PWM/timers MFD driver
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Tomasz Figa <t.figa at samsung.com>
+ *
+ * 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.
+ */
+
+#ifndef MFD_SAMSUNG_PWM_H_
+#define MFD_SAMSUNG_PWM_H_
+
+#include <linux/platform_data/samsung-pwm.h>
+
+#define SAMSUNG_PWM_NUM 5
+
+#define SAMSUNG_PWM_INVERT (1 << 0)
+
+struct platform_device;
+
+struct samsung_pwm {
+ struct samsung_pwm_variant variant;
+ struct device_node *of_node;
+ void __iomem *base;
+ int irq[SAMSUNG_PWM_NUM];
+};
+
+extern void samsung_pwm_start(struct samsung_pwm *pwm,
+ unsigned int channel, bool periodic);
+extern void samsung_pwm_stop(struct samsung_pwm *pwm, unsigned int channel);
+extern void samsung_pwm_setup(struct samsung_pwm *pwm, unsigned int channel,
+ u32 tcmp, u32 tcnt);
+
+extern void samsung_pwm_set_flags(struct samsung_pwm *pwm,
+ unsigned int channel, u32 flags);
+extern void samsung_pwm_set_prescale(struct samsung_pwm *pwm,
+ unsigned int channel, u16 prescale);
+extern void samsung_pwm_set_divisor(struct samsung_pwm *pwm,
+ unsigned int channel, u8 divisor);
+
+extern int samsung_pwm_request(struct samsung_pwm *pwm, unsigned int channel);
+extern void samsung_pwm_free(struct samsung_pwm *pwm, unsigned int channel);
+
+extern struct samsung_pwm *samsung_pwm_get(struct platform_device *pdev);
+
+#endif
diff --git a/include/linux/platform_data/samsung-pwm.h b/include/linux/platform_data/samsung-pwm.h
new file mode 100644
index 0000000..8c48dbb
--- /dev/null
+++ b/include/linux/platform_data/samsung-pwm.h
@@ -0,0 +1,28 @@
+/*
+ * Samsung PWM/timers driver
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Tomasz Figa <t.figa at samsung.com>
+ *
+ * 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.
+ */
+
+#ifndef PLATFORM_DATA_SAMSUNG_PWM_H_
+#define PLATFORM_DATA_SAMSUNG_PWM_H_
+
+struct platform_device;
+
+struct samsung_pwm_variant {
+ u8 bits;
+ u8 div_base;
+ u8 tclk_mask;
+ u8 output_mask;
+ bool has_tint_cstat;
+};
+
+extern int samsung_pwm_register(struct platform_device *pdev);
+
+#endif
--
1.8.1.5
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