[PATCH v4 2/4] ARM: PWM: add allwinner sun8i R40/V40/T3 pwm support.
hao_zhang
hao5781286 at gmail.com
Wed Dec 13 06:44:46 PST 2017
This patch add allwinner sun8i R40/V40/T3 pwm support.
Signed-off-by: hao_zhang <hao5781286 at gmail.com>
---
drivers/pwm/Kconfig | 10 +
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-sun8i-r40.c | 449 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 460 insertions(+)
create mode 100644 drivers/pwm/pwm-sun8i-r40.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 763ee50..cde5a70 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -444,6 +444,16 @@ config PWM_SUN4I
To compile this driver as a module, choose M here: the module
will be called pwm-sun4i.
+config PWM_SUN8I_R40
+ tristate "Allwinner PWM SUN8I R40 support"
+ depends on ARCH_SUNXI || COMPILE_TEST
+ depends on HAS_IOMEM && COMMON_CLK
+ help
+ Generic PWM framework driver for Allwinner SoCs R40, V40, T3.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-sun8i-r40.
+
config PWM_TEGRA
tristate "NVIDIA Tegra PWM support"
depends on ARCH_TEGRA
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 0258a74..026a55b 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_PWM_STM32) += pwm-stm32.o
obj-$(CONFIG_PWM_STM32_LP) += pwm-stm32-lp.o
obj-$(CONFIG_PWM_STMPE) += pwm-stmpe.o
obj-$(CONFIG_PWM_SUN4I) += pwm-sun4i.o
+obj-$(CONFIG_PWM_SUN8I_R40) += pwm-sun8i-r40.o
obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o
obj-$(CONFIG_PWM_TIECAP) += pwm-tiecap.o
obj-$(CONFIG_PWM_TIEHRPWM) += pwm-tiehrpwm.o
diff --git a/drivers/pwm/pwm-sun8i-r40.c b/drivers/pwm/pwm-sun8i-r40.c
new file mode 100644
index 0000000..8df538d
--- /dev/null
+++ b/drivers/pwm/pwm-sun8i-r40.c
@@ -0,0 +1,449 @@
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/jiffies.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/slab.h>
+#include <linux/spinlock.h>
+#include <linux/time.h>
+
+#define PWM_IRQ_ENABLE_REG 0x0000
+#define PCIE(ch) BIT(ch)
+
+#define PWM_IRQ_STATUS_REG 0x0004
+#define PIS(ch) BIT(ch)
+
+#define CAPTURE_IRQ_ENABLE_REG 0x0010
+#define CFIE(ch) BIT(ch << 1 + 1)
+#define CRIE(ch) BIT(ch << 1)
+
+#define CAPTURE_IRQ_STATUS_REG 0x0014
+#define CFIS(ch) BIT(ch << 1 + 1)
+#define CRIS(ch) BIT(ch << 1)
+
+#define CLK_CFG_REG(ch) (0x0020 + (ch >> 1) * 4)
+#define CLK_SRC BIT(7)
+#define CLK_SRC_BYPASS_SEC BIT(6)
+#define CLK_SRC_BYPASS_FIR BIT(5)
+#define CLK_GATING BIT(4)
+#define CLK_DIV_M GENMASK(3, 0)
+
+#define PWM_DZ_CTR_REG(ch) (0x0030 + (ch >> 1) * 4)
+#define PWM_DZ_INTV GENMASK(15, 8)
+#define PWM_DZ_EN BIT(0)
+
+#define PWM_ENABLE_REG 0x0040
+#define PWM_EN(ch) BIT(ch)
+
+#define CAPTURE_ENABLE_REG 0x0044
+#define CAP_EN(ch) BIT(ch)
+
+#define PWM_CTR_REG(ch) (0x0060 + ch * 0x20)
+#define PWM_PERIOD_RDY BIT(11)
+#define PWM_PUL_START BIT(10)
+#define PWM_MODE BIT(9)
+#define PWM_ACT_STA BIT(8)
+#define PWM_PRESCAL_K GENMASK(7, 0)
+
+#define PWM_PERIOD_REG(ch) (0x0064 + ch * 0x20)
+#define PWM_ENTIRE_CYCLE GENMASK(31, 16)
+#define PWM_ACT_CYCLE GENMASK(15, 0)
+
+#define PWM_CNT_REG(ch) (0x0068 + ch * 0x20)
+#define PWM_CNT_VAL GENMASK(15, 0)
+
+#define CAPTURE_CTR_REG(ch) (0x006c + ch * 0x20)
+#define CAPTURE_CRLF BIT(2)
+#define CAPTURE_CFLF BIT(1)
+#define CAPINV BIT(0)
+
+#define CAPTURE_RISE_REG(ch) (0x0070 + ch * 0x20)
+#define CAPTURE_CRLR GENMASK(15, 0)
+
+#define CAPTURE_FALL_REG(ch) (0x0074 + ch * 0x20)
+#define CAPTURE_CFLR GENMASK(15, 0)
+
+struct sunxi_pwm_data {
+ bool has_prescaler_bypass;
+ bool has_rdy;
+ unsigned int npwm;
+};
+
+struct sunxi_pwm_chip {
+ struct pwm_chip chip;
+ struct clk *clk;
+ void __iomem *base;
+ spinlock_t ctrl_lock;
+ const struct sunxi_pwm_data *data;
+};
+
+static const u16 div_m_table[] = {
+ 1,
+ 2,
+ 4,
+ 8,
+ 16,
+ 32,
+ 64,
+ 128,
+ 256
+};
+
+static inline struct sunxi_pwm_chip *to_sunxi_pwm_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct sunxi_pwm_chip, chip);
+}
+
+static inline u32 sunxi_pwm_readl(struct sunxi_pwm_chip *chip,
+ unsigned long offset)
+{
+ return readl(chip->base + offset);
+}
+
+static inline void sunxi_pwm_writel(struct sunxi_pwm_chip *chip,
+ u32 val, unsigned long offset)
+{
+ writel(val, chip->base + offset);
+}
+
+static void sunxi_pwm_set_bit(struct sunxi_pwm_chip *sunxi_pwm,
+ unsigned long reg, u32 bit)
+{
+ u32 val;
+
+ val = sunxi_pwm_readl(sunxi_pwm, reg);
+ val |= bit;
+ sunxi_pwm_writel(sunxi_pwm, val, reg);
+}
+
+static void sunxi_pwm_clear_bit(struct sunxi_pwm_chip *sunxi_pwm,
+ unsigned long reg, u32 bit)
+{
+ u32 val;
+
+ val = sunxi_pwm_readl(sunxi_pwm, reg);
+ val &= ~bit;
+ sunxi_pwm_writel(sunxi_pwm, val, reg);
+}
+
+static void sunxi_pwm_set_value(struct sunxi_pwm_chip *sunxi_pwm,
+ unsigned long reg, u32 mask, u32 val)
+{
+ u32 tmp;
+
+ tmp = sunxi_pwm_readl(sunxi_pwm, reg);
+ tmp &= ~mask;
+ tmp |= mask & val;
+ sunxi_pwm_writel(sunxi_pwm, tmp, reg);
+}
+
+static void sunxi_pwm_set_polarity(struct sunxi_pwm_chip *chip, u32 ch,
+ enum pwm_polarity polarity)
+{
+ if (polarity == PWM_POLARITY_NORMAL)
+ sunxi_pwm_set_bit(chip, PWM_CTR_REG(ch), PWM_ACT_STA);
+ else
+ sunxi_pwm_clear_bit(chip, PWM_CTR_REG(ch), PWM_ACT_STA);
+}
+
+static void sunxi_dump_reg(struct sunxi_pwm_chip *sunxi_pwm, u8 ch)
+{
+ dev_dbg(sunxi_pwm->chip.dev, "ch: %d\n"
+ "\tPWM_IRQ_ENABLE_REG(%04x): \t0x%08x\n"
+ "\tPWM_IRQ_STATUS_REG(%04x): \t0x%08x\n"
+ "\tCAPTURE_IRQ_ENABLE_REG(%04x): \t0x%08x\n"
+ "\tCAPTURE_IRQ_STATUS_REG(%04x): \t0x%08x\n"
+ "\tCLK_CFG_REG(%04x)(%d): \t0x%08x\n"
+ "\tPWM_DZ_CTR_REG(%04x)(%d): \t0x%08x\n"
+ "\tPWM_ENABLE_REG(%04x): \t0x%08x\n"
+ "\tCAPTURE_ENABLE_REG(%04x): \t0x%08x\n"
+ "\tPWM_CTR_REG(%04x)(%d): \t0x%08x\n"
+ "\tPWM_PERIOD_REG(%04x)(%d): \t0x%08x\n"
+ "\tPWM_CNT_REG(%04x)(%d): \t0x%08x\n"
+ "\tCAPTURE_CTR_REG(%04x)(%d): \t0x%08x\n"
+ "\tCAPTURE_RISE_REG(%04x)(%d): \t0x%08x\n"
+ "\tCAPTURE_FALL_REG(%04x)(%d): \t0x%08x\n",
+ ch,
+ PWM_IRQ_ENABLE_REG,
+ readl(sunxi_pwm->base + PWM_IRQ_ENABLE_REG),
+ PWM_IRQ_STATUS_REG,
+ readl(sunxi_pwm->base + PWM_IRQ_STATUS_REG),
+ CAPTURE_IRQ_ENABLE_REG,
+ readl(sunxi_pwm->base + CAPTURE_IRQ_ENABLE_REG),
+ CAPTURE_IRQ_STATUS_REG,
+ readl(sunxi_pwm->base + CAPTURE_IRQ_STATUS_REG),
+ CLK_CFG_REG(ch),
+ ch, readl(sunxi_pwm->base + CLK_CFG_REG(ch)),
+ PWM_DZ_CTR_REG(ch),
+ ch, readl(sunxi_pwm->base + PWM_DZ_CTR_REG(ch)),
+ PWM_ENABLE_REG,
+ readl(sunxi_pwm->base + PWM_ENABLE_REG),
+ CAPTURE_ENABLE_REG,
+ readl(sunxi_pwm->base + CAPTURE_ENABLE_REG),
+ PWM_CTR_REG(ch),
+ ch, readl(sunxi_pwm->base + PWM_CTR_REG(ch)),
+ PWM_PERIOD_REG(ch),
+ ch, readl(sunxi_pwm->base + PWM_PERIOD_REG(ch)),
+ PWM_CNT_REG(ch),
+ ch, readl(sunxi_pwm->base + PWM_CNT_REG(ch)),
+ CAPTURE_CTR_REG(ch),
+ ch, readl(sunxi_pwm->base + CAPTURE_CTR_REG(ch)),
+ CAPTURE_RISE_REG(ch),
+ ch, readl(sunxi_pwm->base + CAPTURE_RISE_REG(ch)),
+ CAPTURE_FALL_REG(ch),
+ ch, readl(sunxi_pwm->base + CAPTURE_FALL_REG(ch)));
+}
+
+static int sunxi_pwm_config(struct sunxi_pwm_chip *sunxi_pwm, u8 ch,
+ struct pwm_state *state)
+{
+ u64 clk_rate, clk_div, val;
+ u16 prescaler = 0;
+ u8 id = 0;
+
+ clk_rate = clk_get_rate(sunxi_pwm->clk);
+ dev_dbg(sunxi_pwm->chip.dev, "clock rate:%lld\n", clk_rate);
+
+ if (clk_rate == 24000000)
+ sunxi_pwm_clear_bit(sunxi_pwm, CLK_CFG_REG(ch), CLK_SRC);
+ else
+ sunxi_pwm_set_bit(sunxi_pwm, CLK_CFG_REG(ch), CLK_SRC);
+
+ if (sunxi_pwm->data->has_prescaler_bypass) {
+ /* pwm output bypass */
+ if (ch % 2)
+ sunxi_pwm_set_bit(sunxi_pwm, CLK_CFG_REG(ch),
+ CLK_SRC_BYPASS_FIR);
+ else
+ sunxi_pwm_set_bit(sunxi_pwm, CLK_CFG_REG(ch),
+ CLK_SRC_BYPASS_SEC);
+ return 0;
+ }
+
+ val = state->period * clk_rate;
+ do_div(val, NSEC_PER_SEC);
+ if (val < 1) {
+ dev_err(sunxi_pwm->chip.dev,
+ "period expects a larger value\n");
+ return -EINVAL;
+ }
+
+ /* calculate and set prescalar, div table, pwn entrie cycle */
+ clk_div = val;
+
+ while (clk_div > 65535) {
+ prescaler++;
+ clk_div = val;
+ do_div(clk_div, prescaler + 1);
+ do_div(clk_div, div_m_table[id]);
+
+ if (prescaler == 255) {
+ prescaler = 0;
+ id++;
+ if (id == 9)
+ return -EINVAL;
+ }
+ }
+
+ sunxi_pwm_set_value(sunxi_pwm, PWM_PERIOD_REG(ch),
+ PWM_ENTIRE_CYCLE, clk_div << 16);
+ sunxi_pwm_set_value(sunxi_pwm, PWM_CTR_REG(ch),
+ PWM_PRESCAL_K, prescaler << 0);
+ sunxi_pwm_set_value(sunxi_pwm, CLK_CFG_REG(ch),
+ CLK_DIV_M, id << 0);
+
+ /* set duty cycle */
+ val = (prescaler + 1) * div_m_table[id] * clk_div;
+ val = state->period;
+ do_div(val, clk_div);
+ clk_div = state->duty_cycle;
+ do_div(clk_div, val);
+
+ sunxi_pwm_set_value(sunxi_pwm, PWM_PERIOD_REG(ch),
+ PWM_ACT_CYCLE, clk_div << 0);
+
+ return 0;
+}
+
+static int sunxi_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ int ret;
+ struct sunxi_pwm_chip *sunxi_pwm = to_sunxi_pwm_chip(chip);
+ struct pwm_state cstate;
+
+ sunxi_dump_reg(sunxi_pwm, pwm->hwpwm);
+ pwm_get_state(pwm, &cstate);
+ if (!cstate.enabled) {
+ ret = clk_prepare_enable(sunxi_pwm->clk);
+ if (ret) {
+ dev_err(chip->dev, "failed to enable PWM clock\n");
+ return ret;
+ }
+ }
+
+ spin_lock(&sunxi_pwm->ctrl_lock);
+
+ if (state->polarity != cstate.polarity)
+ sunxi_pwm_set_polarity(sunxi_pwm, pwm->hwpwm, state->polarity);
+
+ if ((cstate.period != state->period) ||
+ (cstate.duty_cycle != state->duty_cycle)) {
+ ret = sunxi_pwm_config(sunxi_pwm, pwm->hwpwm, state);
+ if (ret) {
+ dev_err(chip->dev, "failed to enable PWM clock\n");
+ return ret;
+ }
+ }
+
+ if (state->enabled) {
+ sunxi_pwm_set_bit(sunxi_pwm,
+ CLK_CFG_REG(pwm->hwpwm), CLK_GATING);
+
+ sunxi_pwm_set_bit(sunxi_pwm,
+ PWM_ENABLE_REG, PWM_EN(pwm->hwpwm));
+ } else {
+ sunxi_pwm_clear_bit(sunxi_pwm,
+ CLK_CFG_REG(pwm->hwpwm), CLK_GATING);
+
+ sunxi_pwm_clear_bit(sunxi_pwm,
+ PWM_ENABLE_REG, PWM_EN(pwm->hwpwm));
+ }
+
+ spin_unlock(&sunxi_pwm->ctrl_lock);
+ sunxi_dump_reg(sunxi_pwm, pwm->hwpwm);
+
+ return 0;
+}
+
+static void sunxi_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct sunxi_pwm_chip *sunxi_pwm = to_sunxi_pwm_chip(chip);
+ u64 clk_rate, tmp;
+ u32 val;
+ u16 clk_div, act_cycle;
+ u8 prescal, id;
+
+ clk_rate = clk_get_rate(sunxi_pwm->clk);
+
+ val = sunxi_pwm_readl(sunxi_pwm, PWM_CTR_REG(pwm->hwpwm));
+ if (PWM_ACT_STA & val)
+ state->polarity = PWM_POLARITY_NORMAL;
+ else
+ state->polarity = PWM_POLARITY_INVERSED;
+
+ prescal = PWM_PRESCAL_K & val;
+
+ val = sunxi_pwm_readl(sunxi_pwm, PWM_ENABLE_REG);
+ if (PWM_EN(pwm->hwpwm) & val)
+ state->enabled = true;
+ else
+ state->enabled = false;
+
+ val = sunxi_pwm_readl(sunxi_pwm, PWM_PERIOD_REG(pwm->hwpwm));
+ act_cycle = PWM_ACT_CYCLE & val;
+ clk_div = val >> 16;
+
+ val = sunxi_pwm_readl(sunxi_pwm, CLK_CFG_REG(pwm->hwpwm));
+ id = CLK_DIV_M & val;
+
+ tmp = act_cycle * prescal * div_m_table[id] * NSEC_PER_SEC;
+ state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+ tmp = clk_div * prescal * div_m_table[id] * NSEC_PER_SEC;
+ state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+}
+
+static const struct pwm_ops sunxi_pwm_ops = {
+ .apply = sunxi_pwm_apply,
+ .get_state = sunxi_pwm_get_state,
+ .owner = THIS_MODULE,
+};
+
+static const struct sunxi_pwm_data sunxi_pwm_data_r40 = {
+ .has_prescaler_bypass = false,
+ .has_rdy = true,
+ .npwm = 8,
+};
+
+static const struct of_device_id sunxi_pwm_dt_ids[] = {
+ {
+ .compatible = "allwinner,sun8i-r40-pwm",
+ .data = &sunxi_pwm_data_r40,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sunxi_pwm_dt_ids);
+
+static int sunxi_pwm_probe(struct platform_device *pdev)
+{
+ struct sunxi_pwm_chip *pwm;
+ struct resource *res;
+ int ret;
+ const struct of_device_id *match;
+
+ match = of_match_device(sunxi_pwm_dt_ids, &pdev->dev);
+
+ pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+ if (!pwm)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pwm->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pwm->base))
+ return PTR_ERR(pwm->base);
+
+ pwm->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(pwm->clk))
+ return PTR_ERR(pwm->clk);
+
+ pwm->data = match->data;
+ pwm->chip.dev = &pdev->dev;
+ pwm->chip.ops = &sunxi_pwm_ops;
+ pwm->chip.base = -1;
+ pwm->chip.npwm = pwm->data->npwm;
+ pwm->chip.of_xlate = of_pwm_xlate_with_flags;
+ pwm->chip.of_pwm_n_cells = 3;
+
+ dev_dbg(pwm->chip.dev, "npwm: %d\n", pwm->chip.npwm);
+
+ spin_lock_init(&pwm->ctrl_lock);
+
+ ret = pwmchip_add(&pwm->chip);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, pwm);
+
+ return 0;
+}
+
+static int sunxi_pwm_remove(struct platform_device *pdev)
+{
+ struct sunxi_pwm_chip *pwm = platform_get_drvdata(pdev);
+
+ return pwmchip_remove(&pwm->chip);
+}
+
+static struct platform_driver sunxi_pwm_driver = {
+ .driver = {
+ .name = "sun8i-r40-pwm",
+ .of_match_table = sunxi_pwm_dt_ids,
+ },
+ .probe = sunxi_pwm_probe,
+ .remove = sunxi_pwm_remove,
+};
+module_platform_driver(sunxi_pwm_driver);
+
+MODULE_ALIAS("platform:sun8i-r40-pwm");
+MODULE_AUTHOR("Hao Zhang <hao5781286 at gmail.com>");
+MODULE_DESCRIPTION("Allwinner sun8i-r40 PWM driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4
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