lkml.org 
[lkml]   [2018]   [Nov]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH v3 6/6] ARM: PWM: add allwinner sun8i R40/T3/V40 PWM support.
The sun8i R40/T3/V40 PWM has 8 PWM channals and divides to 4 PWM pairs,
each PWM pair built-in 1 clock module, 2 timer logic module and 1
programmable dead-time generator, it also support waveform capture.
It has 2 clock sources OSC24M and APB1, it is different with the
sun4i-pwm driver, Therefore add a new driver for it.

Signed-off-by: Hao Zhang <hao5781286@gmail.com>
---
drivers/pwm/Kconfig | 12 +-
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-sun8i.c | 418 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 430 insertions(+), 1 deletion(-)
create mode 100644 drivers/pwm/pwm-sun8i.c

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 504d252..6105ac8 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -426,7 +426,7 @@ config PWM_STMPE
expanders.

config PWM_SUN4I
- tristate "Allwinner PWM support"
+ tristate "Allwinner SUN4I PWM support"
depends on ARCH_SUNXI || COMPILE_TEST
depends on HAS_IOMEM && COMMON_CLK
help
@@ -435,6 +435,16 @@ config PWM_SUN4I
To compile this driver as a module, choose M here: the module
will be called pwm-sun4i.

+config PWM_SUN8I
+ tristate "Allwinner SUN8I (R40/V40/T3) PWM support"
+ depends on ARCH_SUNXI || COMPILE_TEST
+ depends on HAS_IOMEM && COMMON_CLK
+ help
+ Generic PWM framework driver for Allwinner R40/V40/T3 SoCs.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-sun8i.
+
config PWM_TEGRA
tristate "NVIDIA Tegra PWM support"
depends on ARCH_TEGRA
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 9c676a0..32c8d2d 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -43,6 +43,7 @@ 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-$(CONFIG_PWM_SUN8I) += pwm-sun8i.o
obj-$(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.c b/drivers/pwm/pwm-sun8i.c
new file mode 100644
index 0000000..d8597e4
--- /dev/null
+++ b/drivers/pwm/pwm-sun8i.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hao Zhang <hao5781286@gmail.com>
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#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/slab.h>
+#include <linux/spinlock.h>
+#include <linux/time.h>
+#include <linux/regmap.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 CRIE(ch) BIT((ch) * 2)
+#define CFIE(ch) BIT((ch) * 2 + 1)
+
+#define CAPTURE_IRQ_STATUS_REG 0x0014
+#define CRIS(ch) BIT((ch) * 2)
+#define CFIS(ch) BIT((ch) * 2 + 1)
+
+#define CLK_CFG_REG(ch) (0x0020 + ((ch) >> 1) * 4)
+#define CLK_SRC_SEL GENMASK(8, 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 sun8i_pwm_chip {
+ struct pwm_chip chip;
+ struct clk *clk;
+ void __iomem *base;
+ const struct sun8i_pwm_data *data;
+ struct regmap *regmap;
+};
+
+static struct sun8i_pwm_chip *to_sun8i_pwm_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct sun8i_pwm_chip, chip);
+}
+
+static u32 sun8i_pwm_read(struct sun8i_pwm_chip *sun8i_pwm,
+ unsigned long offset)
+{
+ u32 val;
+
+ regmap_read(sun8i_pwm->regmap, offset, &val);
+ return val;
+}
+
+static void sun8i_pwm_set_bit(struct sun8i_pwm_chip *sun8i_pwm,
+ unsigned long reg, u32 bit)
+{
+ regmap_update_bits(sun8i_pwm->regmap, reg, bit, bit);
+}
+
+static void sun8i_pwm_clear_bit(struct sun8i_pwm_chip *sun8i_pwm,
+ unsigned long reg, u32 bit)
+{
+ regmap_update_bits(sun8i_pwm->regmap, reg, bit, 0);
+}
+
+static void sun8i_pwm_set_value(struct sun8i_pwm_chip *sun8i_pwm,
+ unsigned long reg, u32 mask, u32 val)
+{
+ regmap_update_bits(sun8i_pwm->regmap, reg, mask, val);
+}
+
+static void sun8i_pwm_set_polarity(struct sun8i_pwm_chip *chip, u32 ch,
+ enum pwm_polarity polarity)
+{
+ if (polarity == PWM_POLARITY_NORMAL)
+ sun8i_pwm_set_bit(chip, PWM_CTR_REG(ch), PWM_ACT_STA);
+ else
+ sun8i_pwm_clear_bit(chip, PWM_CTR_REG(ch), PWM_ACT_STA);
+}
+
+static int sun8i_pwm_config(struct sun8i_pwm_chip *sun8i_pwm, u8 ch,
+ struct pwm_state *state)
+{
+ u64 clk_rate, clk_div, val;
+ u16 prescaler = 0;
+ u16 div_id = 0;
+ struct clk *clk;
+ bool is_clk;
+ int ret;
+
+ clk_rate = clk_get_rate(sun8i_pwm->clk);
+
+ /* check period and select clock source */
+ val = state->period * clk_rate;
+ do_div(val, NSEC_PER_SEC);
+ is_clk = devm_clk_name_match(sun8i_pwm->clk, "mux-0");
+ if (val <= 1 && is_clk) {
+ clk = devm_clk_get(sun8i_pwm->chip.dev, "mux-1");
+ if (IS_ERR(clk)) {
+ dev_err(sun8i_pwm->chip.dev,
+ "Period expects a larger value\n");
+ return -EINVAL;
+ }
+
+ clk_rate = clk_get_rate(clk);
+ val = state->period * clk_rate;
+ do_div(val, NSEC_PER_SEC);
+ if (val <= 1) {
+ dev_err(sun8i_pwm->chip.dev,
+ "Period expects a larger value\n");
+ return -EINVAL;
+ }
+
+ /* change clock source to "mux-1" */
+ clk_disable_unprepare(sun8i_pwm->clk);
+ devm_clk_put(sun8i_pwm->chip.dev, sun8i_pwm->clk);
+ sun8i_pwm->clk = clk;
+
+ ret = clk_prepare_enable(sun8i_pwm->clk);
+ if (ret) {
+ dev_err(sun8i_pwm->chip.dev,
+ "Failed to enable PWM clock\n");
+ return ret;
+ }
+
+ } else {
+ dev_err(sun8i_pwm->chip.dev,
+ "Period expects a larger value\n");
+ return -EINVAL;
+ }
+
+ is_clk = devm_clk_name_match(sun8i_pwm->clk, "mux-0");
+ if (is_clk)
+ sun8i_pwm_set_value(sun8i_pwm, CLK_CFG_REG(ch),
+ CLK_SRC_SEL, 0 << 7);
+ else
+ sun8i_pwm_set_value(sun8i_pwm, CLK_CFG_REG(ch),
+ CLK_SRC_SEL, 1 << 7);
+
+ dev_info(sun8i_pwm->chip.dev, "clock source freq:%lldHz\n", clk_rate);
+
+ /* calculate and set prescaler, div table, PWM entire cycle */
+ clk_div = val;
+ while (clk_div > 65535) {
+ prescaler++;
+ clk_div = val;
+ do_div(clk_div, 1U << div_id);
+ do_div(clk_div, prescaler + 1);
+
+ if (prescaler == 255) {
+ prescaler = 0;
+ div_id++;
+ if (div_id == 9) {
+ dev_err(sun8i_pwm->chip.dev,
+ "unsupport period value\n");
+ return -EINVAL;
+ }
+ }
+ }
+
+ sun8i_pwm_set_value(sun8i_pwm, PWM_PERIOD_REG(ch),
+ PWM_ENTIRE_CYCLE, clk_div << 16);
+ sun8i_pwm_set_value(sun8i_pwm, PWM_CTR_REG(ch),
+ PWM_PRESCAL_K, prescaler << 0);
+ sun8i_pwm_set_value(sun8i_pwm, CLK_CFG_REG(ch),
+ CLK_DIV_M, div_id << 0);
+
+ /* set duty cycle */
+ val = state->period;
+ do_div(val, clk_div);
+ clk_div = state->duty_cycle;
+ do_div(clk_div, val);
+ if (clk_div > 65535)
+ clk_div = 65535;
+
+ sun8i_pwm_set_value(sun8i_pwm, PWM_PERIOD_REG(ch),
+ PWM_ACT_CYCLE, clk_div << 0);
+
+ return 0;
+}
+
+static int sun8i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ int ret;
+ struct sun8i_pwm_chip *sun8i_pwm = to_sun8i_pwm_chip(chip);
+ struct pwm_state cstate;
+
+ pwm_get_state(pwm, &cstate);
+ if (!cstate.enabled) {
+ ret = clk_prepare_enable(sun8i_pwm->clk);
+ if (ret) {
+ dev_err(chip->dev, "Failed to enable PWM clock\n");
+ return ret;
+ }
+ }
+
+ if ((cstate.period != state->period) ||
+ (cstate.duty_cycle != state->duty_cycle)) {
+ ret = sun8i_pwm_config(sun8i_pwm, pwm->hwpwm, state);
+ if (ret) {
+ dev_err(chip->dev, "Failed to config PWM\n");
+ return ret;
+ }
+ }
+
+ if (state->polarity != cstate.polarity)
+ sun8i_pwm_set_polarity(sun8i_pwm, pwm->hwpwm, state->polarity);
+
+ if (state->enabled) {
+ sun8i_pwm_set_bit(sun8i_pwm,
+ CLK_CFG_REG(pwm->hwpwm), CLK_GATING);
+
+ sun8i_pwm_set_bit(sun8i_pwm,
+ PWM_ENABLE_REG, PWM_EN(pwm->hwpwm));
+ } else {
+ sun8i_pwm_clear_bit(sun8i_pwm,
+ CLK_CFG_REG(pwm->hwpwm), CLK_GATING);
+
+ sun8i_pwm_clear_bit(sun8i_pwm,
+ PWM_ENABLE_REG, PWM_EN(pwm->hwpwm));
+ }
+
+ return 0;
+}
+
+static void sun8i_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct sun8i_pwm_chip *sun8i_pwm = to_sun8i_pwm_chip(chip);
+ u64 clk_rate, tmp;
+ u32 val;
+ u16 clk_div, act_cycle;
+ u8 prescal, div_id;
+ u8 chn = pwm->hwpwm;
+
+ clk_rate = clk_get_rate(sun8i_pwm->clk);
+
+ val = sun8i_pwm_read(sun8i_pwm, PWM_CTR_REG(chn));
+ if (PWM_ACT_STA & val)
+ state->polarity = PWM_POLARITY_NORMAL;
+ else
+ state->polarity = PWM_POLARITY_INVERSED;
+
+ prescal = PWM_PRESCAL_K & val;
+
+ val = sun8i_pwm_read(sun8i_pwm, PWM_ENABLE_REG);
+ if (PWM_EN(chn) & val)
+ state->enabled = true;
+ else
+ state->enabled = false;
+
+ val = sun8i_pwm_read(sun8i_pwm, PWM_PERIOD_REG(chn));
+ act_cycle = PWM_ACT_CYCLE & val;
+ clk_div = val >> 16;
+
+ val = sun8i_pwm_read(sun8i_pwm, CLK_CFG_REG(chn));
+ div_id = CLK_DIV_M & val;
+
+ tmp = act_cycle * prescal * (1U << div_id) * NSEC_PER_SEC;
+ state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+ tmp = clk_div * prescal * (1U << div_id) * NSEC_PER_SEC;
+ state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+}
+
+static const struct regmap_config sun8i_pwm_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .max_register = CAPTURE_FALL_REG(7),
+};
+
+static const struct pwm_ops sun8i_pwm_ops = {
+ .apply = sun8i_pwm_apply,
+ .get_state = sun8i_pwm_get_state,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id sun8i_pwm_dt_ids[] = {
+ {
+ .compatible = "allwinner,sun8i-r40-pwm",
+ .data = NULL,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sun8i_pwm_dt_ids);
+
+static int sun8i_pwm_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct sun8i_pwm_chip *pwm;
+ struct resource *res;
+ int ret;
+ const struct of_device_id *match;
+
+ match = of_match_device(sun8i_pwm_dt_ids, &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+
+ 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->regmap = devm_regmap_init_mmio(&pdev->dev, pwm->base,
+ &sun8i_pwm_regmap_config);
+ if (IS_ERR(pwm->regmap)) {
+ dev_err(&pdev->dev, "Failed to create regmap\n");
+ return PTR_ERR(pwm->regmap);
+ }
+
+ /* we use mux-0 as default clock source */
+ pwm->clk = devm_clk_get(&pdev->dev, "mux-0");
+ if (IS_ERR(pwm->clk)) {
+ pwm->clk = devm_clk_get(&pdev->dev, "mux-1");
+ if (IS_ERR(pwm->clk)) {
+ dev_err(&pdev->dev, "Failed to get PWM clock\n");
+ return PTR_ERR(pwm->clk);
+ }
+ }
+
+ ret = of_property_read_u32(np, "pwm-channels", &pwm->chip.npwm);
+ if (ret && !pwm->chip.npwm) {
+ dev_err(&pdev->dev, "Can't get pwm-channels\n");
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "pwm-channels:%d\n", pwm->chip.npwm);
+ pwm->data = match->data;
+ pwm->chip.dev = &pdev->dev;
+ pwm->chip.ops = &sun8i_pwm_ops;
+ pwm->chip.base = -1;
+ pwm->chip.of_xlate = of_pwm_xlate_with_flags;
+ pwm->chip.of_pwm_n_cells = 3;
+
+ 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 sun8i_pwm_remove(struct platform_device *pdev)
+{
+ struct sun8i_pwm_chip *pwm = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(pwm->clk);
+ return pwmchip_remove(&pwm->chip);
+}
+
+static struct platform_driver sun8i_pwm_driver = {
+ .driver = {
+ .name = "sun8i-pwm",
+ .of_match_table = sun8i_pwm_dt_ids,
+ },
+ .probe = sun8i_pwm_probe,
+ .remove = sun8i_pwm_remove,
+};
+module_platform_driver(sun8i_pwm_driver);
+
+MODULE_ALIAS("platform: sun8i-pwm");
+MODULE_AUTHOR("Hao Zhang <hao5781286@gmail.com>");
+MODULE_DESCRIPTION("Allwinner sun8i PWM driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4
\
 
 \ /
  Last update: 2018-11-25 17:24    [W:0.161 / U:1.528 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site