Commit 2c87f7a3 authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'pwm/for-5.12-rc1' of...

Merge tag 'pwm/for-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "The ZTE ZX platform is being removed, so the PWM driver is no longer
  needed and removed as well.

  Other than that this contains a small set of fixes and cleanups across
  a couple of drivers"

* tag 'pwm/for-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: lpc18xx-sct: remove unneeded semicolon
  pwm: iqs620a: Correct a stale state variable
  pwm: iqs620a: Fix overflow and optimize calculations
  pwm: rockchip: Enable clock before calling clk_get_rate()
  pwm: rockchip: Eliminate potential race condition when probing
  pwm: rockchip: Replace "bus clk" with "PWM clk"
  pwm: rockchip: rockchip_pwm_probe(): Remove superfluous clk_unprepare()
  pwm: rockchip: Enable APB clock during register access while probing
  pwm: Remove ZTE ZX driver
parents ffc17596 9a9dd7e4
ZTE ZX PWM controller
Required properties:
- compatible: Should be "zte,zx296718-pwm".
- reg: Physical base address and length of the controller's registers.
- clocks : The phandle and specifier referencing the controller's clocks.
- clock-names: "pclk" for PCLK, "wclk" for WCLK to the PWM controller. The
PCLK is for register access, while WCLK is the reference clock for
calculating period and duty cycles.
- #pwm-cells: Should be 3. See pwm.yaml in this directory for a description of
the cells format.
Example:
pwm: pwm@1439000 {
compatible = "zte,zx296718-pwm";
reg = <0x1439000 0x1000>;
clocks = <&lsp1crm LSP1_PWM_PCLK>,
<&lsp1crm LSP1_PWM_WCLK>;
clock-names = "pclk", "wclk";
#pwm-cells = <3>;
};
......@@ -611,14 +611,4 @@ config PWM_VT8500
To compile this driver as a module, choose M here: the module
will be called pwm-vt8500.
config PWM_ZX
tristate "ZTE ZX PWM support"
depends on ARCH_ZX || COMPILE_TEST
depends on HAS_IOMEM
help
Generic PWM framework driver for ZTE ZX family SoCs.
To compile this driver as a module, choose M here: the module
will be called pwm-zx.
endif
......@@ -57,4 +57,3 @@ obj-$(CONFIG_PWM_TIEHRPWM) += pwm-tiehrpwm.o
obj-$(CONFIG_PWM_TWL) += pwm-twl.o
obj-$(CONFIG_PWM_TWL_LED) += pwm-twl-led.o
obj-$(CONFIG_PWM_VT8500) += pwm-vt8500.o
obj-$(CONFIG_PWM_ZX) += pwm-zx.o
......@@ -37,16 +37,34 @@ struct iqs620_pwm_private {
struct pwm_chip chip;
struct notifier_block notifier;
struct mutex lock;
bool out_en;
u8 duty_val;
unsigned int duty_scale;
};
static int iqs620_pwm_init(struct iqs620_pwm_private *iqs620_pwm,
unsigned int duty_scale)
{
struct iqs62x_core *iqs62x = iqs620_pwm->iqs62x;
int ret;
if (!duty_scale)
return regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
IQS620_PWR_SETTINGS_PWM_OUT, 0);
ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
duty_scale - 1);
if (ret)
return ret;
return regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
IQS620_PWR_SETTINGS_PWM_OUT, 0xff);
}
static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
const struct pwm_state *state)
{
struct iqs620_pwm_private *iqs620_pwm;
struct iqs62x_core *iqs62x;
u64 duty_scale;
unsigned int duty_cycle;
unsigned int duty_scale;
int ret;
if (state->polarity != PWM_POLARITY_NORMAL)
......@@ -56,7 +74,6 @@ static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
iqs620_pwm = container_of(chip, struct iqs620_pwm_private, chip);
iqs62x = iqs620_pwm->iqs62x;
/*
* The duty cycle generated by the device is calculated as follows:
......@@ -70,38 +87,18 @@ static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
* For lower duty cycles (e.g. 0), the PWM output is simply disabled to
* allow an external pull-down resistor to hold the GPIO3/LTX pin low.
*/
duty_scale = div_u64(state->duty_cycle * 256, IQS620_PWM_PERIOD_NS);
mutex_lock(&iqs620_pwm->lock);
if (!state->enabled || !duty_scale) {
ret = regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
IQS620_PWR_SETTINGS_PWM_OUT, 0);
if (ret)
goto err_mutex;
}
if (duty_scale) {
u8 duty_val = min_t(u64, duty_scale - 1, 0xff);
duty_cycle = min_t(u64, state->duty_cycle, IQS620_PWM_PERIOD_NS);
duty_scale = duty_cycle * 256 / IQS620_PWM_PERIOD_NS;
ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
duty_val);
if (ret)
goto err_mutex;
if (!state->enabled)
duty_scale = 0;
iqs620_pwm->duty_val = duty_val;
}
if (state->enabled && duty_scale) {
ret = regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
IQS620_PWR_SETTINGS_PWM_OUT, 0xff);
if (ret)
goto err_mutex;
}
mutex_lock(&iqs620_pwm->lock);
iqs620_pwm->out_en = state->enabled;
ret = iqs620_pwm_init(iqs620_pwm, duty_scale);
if (!ret)
iqs620_pwm->duty_scale = duty_scale;
err_mutex:
mutex_unlock(&iqs620_pwm->lock);
return ret;
......@@ -119,12 +116,11 @@ static void iqs620_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
/*
* Since the device cannot generate a 0% duty cycle, requests to do so
* cause subsequent calls to iqs620_pwm_get_state to report the output
* as disabled with duty cycle equal to that which was in use prior to
* the request. This is not ideal, but is the best compromise based on
* as disabled. This is not ideal, but is the best compromise based on
* the capabilities of the device.
*/
state->enabled = iqs620_pwm->out_en;
state->duty_cycle = DIV_ROUND_UP((iqs620_pwm->duty_val + 1) *
state->enabled = iqs620_pwm->duty_scale > 0;
state->duty_cycle = DIV_ROUND_UP(iqs620_pwm->duty_scale *
IQS620_PWM_PERIOD_NS, 256);
mutex_unlock(&iqs620_pwm->lock);
......@@ -136,7 +132,6 @@ static int iqs620_pwm_notifier(struct notifier_block *notifier,
unsigned long event_flags, void *context)
{
struct iqs620_pwm_private *iqs620_pwm;
struct iqs62x_core *iqs62x;
int ret;
if (!(event_flags & BIT(IQS62X_EVENT_SYS_RESET)))
......@@ -144,7 +139,6 @@ static int iqs620_pwm_notifier(struct notifier_block *notifier,
iqs620_pwm = container_of(notifier, struct iqs620_pwm_private,
notifier);
iqs62x = iqs620_pwm->iqs62x;
mutex_lock(&iqs620_pwm->lock);
......@@ -153,16 +147,8 @@ static int iqs620_pwm_notifier(struct notifier_block *notifier,
* of a device reset, so nothing else is printed here unless there is
* an additional failure.
*/
ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
iqs620_pwm->duty_val);
if (ret)
goto err_mutex;
ret = regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
IQS620_PWR_SETTINGS_PWM_OUT,
iqs620_pwm->out_en ? 0xff : 0);
ret = iqs620_pwm_init(iqs620_pwm, iqs620_pwm->duty_scale);
err_mutex:
mutex_unlock(&iqs620_pwm->lock);
if (ret) {
......@@ -209,12 +195,14 @@ static int iqs620_pwm_probe(struct platform_device *pdev)
ret = regmap_read(iqs62x->regmap, IQS620_PWR_SETTINGS, &val);
if (ret)
return ret;
iqs620_pwm->out_en = val & IQS620_PWR_SETTINGS_PWM_OUT;
if (val & IQS620_PWR_SETTINGS_PWM_OUT) {
ret = regmap_read(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE, &val);
if (ret)
return ret;
iqs620_pwm->duty_val = val;
iqs620_pwm->duty_scale = val + 1;
}
iqs620_pwm->chip.dev = &pdev->dev;
iqs620_pwm->chip.ops = &iqs620_pwm_ops;
......
......@@ -289,7 +289,7 @@ static int lpc18xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
dev_err(lpc18xx_pwm->dev,
"maximum number of simultaneous channels reached\n");
return -EBUSY;
};
}
set_bit(event, &lpc18xx_pwm->event_map);
lpc18xx_data->duty_event = event;
......
......@@ -72,6 +72,10 @@ static void rockchip_pwm_get_state(struct pwm_chip *chip,
if (ret)
return;
ret = clk_enable(pc->clk);
if (ret)
return;
clk_rate = clk_get_rate(pc->clk);
tmp = readl_relaxed(pc->base + pc->data->regs.period);
......@@ -90,6 +94,7 @@ static void rockchip_pwm_get_state(struct pwm_chip *chip,
else
state->polarity = PWM_POLARITY_NORMAL;
clk_disable(pc->clk);
clk_disable(pc->pclk);
}
......@@ -189,6 +194,10 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
if (ret)
return ret;
ret = clk_enable(pc->clk);
if (ret)
return ret;
pwm_get_state(pwm, &curstate);
enabled = curstate.enabled;
......@@ -208,6 +217,7 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
}
out:
clk_disable(pc->clk);
clk_disable(pc->pclk);
return ret;
......@@ -288,6 +298,7 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
const struct of_device_id *id;
struct rockchip_pwm_chip *pc;
u32 enable_conf, ctrl;
bool enabled;
int ret, count;
id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);
......@@ -307,7 +318,7 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
pc->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(pc->clk))
return dev_err_probe(&pdev->dev, PTR_ERR(pc->clk),
"Can't get bus clk\n");
"Can't get PWM clk\n");
}
count = of_count_phandle_with_args(pdev->dev.of_node,
......@@ -326,13 +337,13 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
ret = clk_prepare_enable(pc->clk);
if (ret) {
dev_err(&pdev->dev, "Can't prepare enable bus clk: %d\n", ret);
dev_err(&pdev->dev, "Can't prepare enable PWM clk: %d\n", ret);
return ret;
}
ret = clk_prepare(pc->pclk);
ret = clk_prepare_enable(pc->pclk);
if (ret) {
dev_err(&pdev->dev, "Can't prepare APB clk: %d\n", ret);
dev_err(&pdev->dev, "Can't prepare enable APB clk: %d\n", ret);
goto err_clk;
}
......@@ -349,23 +360,26 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
pc->chip.of_pwm_n_cells = 3;
}
enable_conf = pc->data->enable_conf;
ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
enabled = (ctrl & enable_conf) == enable_conf;
ret = pwmchip_add(&pc->chip);
if (ret < 0) {
clk_unprepare(pc->clk);
dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
goto err_pclk;
}
/* Keep the PWM clk enabled if the PWM appears to be up and running. */
enable_conf = pc->data->enable_conf;
ctrl = readl_relaxed(pc->base + pc->data->regs.ctrl);
if ((ctrl & enable_conf) != enable_conf)
if (!enabled)
clk_disable(pc->clk);
clk_disable(pc->pclk);
return 0;
err_pclk:
clk_unprepare(pc->pclk);
clk_disable_unprepare(pc->pclk);
err_clk:
clk_disable_unprepare(pc->clk);
......
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2017 Sanechips Technology Co., Ltd.
* Copyright 2017 Linaro Ltd.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/slab.h>
#define ZX_PWM_MODE 0x0
#define ZX_PWM_CLKDIV_SHIFT 2
#define ZX_PWM_CLKDIV_MASK GENMASK(11, 2)
#define ZX_PWM_CLKDIV(x) (((x) << ZX_PWM_CLKDIV_SHIFT) & \
ZX_PWM_CLKDIV_MASK)
#define ZX_PWM_POLAR BIT(1)
#define ZX_PWM_EN BIT(0)
#define ZX_PWM_PERIOD 0x4
#define ZX_PWM_DUTY 0x8
#define ZX_PWM_CLKDIV_MAX 1023
#define ZX_PWM_PERIOD_MAX 65535
struct zx_pwm_chip {
struct pwm_chip chip;
struct clk *pclk;
struct clk *wclk;
void __iomem *base;
};
static inline struct zx_pwm_chip *to_zx_pwm_chip(struct pwm_chip *chip)
{
return container_of(chip, struct zx_pwm_chip, chip);
}
static inline u32 zx_pwm_readl(struct zx_pwm_chip *zpc, unsigned int hwpwm,
unsigned int offset)
{
return readl(zpc->base + (hwpwm + 1) * 0x10 + offset);
}
static inline void zx_pwm_writel(struct zx_pwm_chip *zpc, unsigned int hwpwm,
unsigned int offset, u32 value)
{
writel(value, zpc->base + (hwpwm + 1) * 0x10 + offset);
}
static void zx_pwm_set_mask(struct zx_pwm_chip *zpc, unsigned int hwpwm,
unsigned int offset, u32 mask, u32 value)
{
u32 data;
data = zx_pwm_readl(zpc, hwpwm, offset);
data &= ~mask;
data |= value & mask;
zx_pwm_writel(zpc, hwpwm, offset, data);
}
static void zx_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
struct pwm_state *state)
{
struct zx_pwm_chip *zpc = to_zx_pwm_chip(chip);
unsigned long rate;
unsigned int div;
u32 value;
u64 tmp;
value = zx_pwm_readl(zpc, pwm->hwpwm, ZX_PWM_MODE);
if (value & ZX_PWM_POLAR)
state->polarity = PWM_POLARITY_NORMAL;
else
state->polarity = PWM_POLARITY_INVERSED;
if (value & ZX_PWM_EN)
state->enabled = true;
else
state->enabled = false;
div = (value & ZX_PWM_CLKDIV_MASK) >> ZX_PWM_CLKDIV_SHIFT;
rate = clk_get_rate(zpc->wclk);
tmp = zx_pwm_readl(zpc, pwm->hwpwm, ZX_PWM_PERIOD);
tmp *= div * NSEC_PER_SEC;
state->period = DIV_ROUND_CLOSEST_ULL(tmp, rate);
tmp = zx_pwm_readl(zpc, pwm->hwpwm, ZX_PWM_DUTY);
tmp *= div * NSEC_PER_SEC;
state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, rate);
}
static int zx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned int duty_ns, unsigned int period_ns)
{
struct zx_pwm_chip *zpc = to_zx_pwm_chip(chip);
unsigned int period_cycles, duty_cycles;
unsigned long long c;
unsigned int div = 1;
unsigned long rate;
/* Find out the best divider */
rate = clk_get_rate(zpc->wclk);
while (1) {
c = rate / div;
c = c * period_ns;
do_div(c, NSEC_PER_SEC);
if (c < ZX_PWM_PERIOD_MAX)
break;
div++;
if (div > ZX_PWM_CLKDIV_MAX)
return -ERANGE;
}
/* Calculate duty cycles */
period_cycles = c;
c *= duty_ns;
do_div(c, period_ns);
duty_cycles = c;
/*
* If the PWM is being enabled, we have to temporarily disable it
* before configuring the registers.
*/
if (pwm_is_enabled(pwm))
zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE, ZX_PWM_EN, 0);
/* Set up registers */
zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE, ZX_PWM_CLKDIV_MASK,
ZX_PWM_CLKDIV(div));
zx_pwm_writel(zpc, pwm->hwpwm, ZX_PWM_PERIOD, period_cycles);
zx_pwm_writel(zpc, pwm->hwpwm, ZX_PWM_DUTY, duty_cycles);
/* Re-enable the PWM if needed */
if (pwm_is_enabled(pwm))
zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE,
ZX_PWM_EN, ZX_PWM_EN);
return 0;
}
static int zx_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
const struct pwm_state *state)
{
struct zx_pwm_chip *zpc = to_zx_pwm_chip(chip);
struct pwm_state cstate;
int ret;
pwm_get_state(pwm, &cstate);
if (state->polarity != cstate.polarity)
zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE, ZX_PWM_POLAR,
(state->polarity == PWM_POLARITY_INVERSED) ?
0 : ZX_PWM_POLAR);
if (state->period != cstate.period ||
state->duty_cycle != cstate.duty_cycle) {
ret = zx_pwm_config(chip, pwm, state->duty_cycle,
state->period);
if (ret)
return ret;
}
if (state->enabled != cstate.enabled) {
if (state->enabled) {
ret = clk_prepare_enable(zpc->wclk);
if (ret)
return ret;
zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE,
ZX_PWM_EN, ZX_PWM_EN);
} else {
zx_pwm_set_mask(zpc, pwm->hwpwm, ZX_PWM_MODE,
ZX_PWM_EN, 0);
clk_disable_unprepare(zpc->wclk);
}
}
return 0;
}
static const struct pwm_ops zx_pwm_ops = {
.apply = zx_pwm_apply,
.get_state = zx_pwm_get_state,
.owner = THIS_MODULE,
};
static int zx_pwm_probe(struct platform_device *pdev)
{
struct zx_pwm_chip *zpc;
unsigned int i;
int ret;
zpc = devm_kzalloc(&pdev->dev, sizeof(*zpc), GFP_KERNEL);
if (!zpc)
return -ENOMEM;
zpc->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(zpc->base))
return PTR_ERR(zpc->base);
zpc->pclk = devm_clk_get(&pdev->dev, "pclk");
if (IS_ERR(zpc->pclk))
return PTR_ERR(zpc->pclk);
zpc->wclk = devm_clk_get(&pdev->dev, "wclk");
if (IS_ERR(zpc->wclk))
return PTR_ERR(zpc->wclk);
ret = clk_prepare_enable(zpc->pclk);
if (ret)
return ret;
zpc->chip.dev = &pdev->dev;
zpc->chip.ops = &zx_pwm_ops;
zpc->chip.base = -1;
zpc->chip.npwm = 4;
zpc->chip.of_xlate = of_pwm_xlate_with_flags;
zpc->chip.of_pwm_n_cells = 3;
/*
* PWM devices may be enabled by firmware, and let's disable all of
* them initially to save power.
*/
for (i = 0; i < zpc->chip.npwm; i++)
zx_pwm_set_mask(zpc, i, ZX_PWM_MODE, ZX_PWM_EN, 0);
ret = pwmchip_add(&zpc->chip);
if (ret < 0) {
dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
clk_disable_unprepare(zpc->pclk);
return ret;
}
platform_set_drvdata(pdev, zpc);
return 0;
}
static int zx_pwm_remove(struct platform_device *pdev)
{
struct zx_pwm_chip *zpc = platform_get_drvdata(pdev);
int ret;
ret = pwmchip_remove(&zpc->chip);
clk_disable_unprepare(zpc->pclk);
return ret;
}
static const struct of_device_id zx_pwm_dt_ids[] = {
{ .compatible = "zte,zx296718-pwm", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, zx_pwm_dt_ids);
static struct platform_driver zx_pwm_driver = {
.driver = {
.name = "zx-pwm",
.of_match_table = zx_pwm_dt_ids,
},
.probe = zx_pwm_probe,
.remove = zx_pwm_remove,
};
module_platform_driver(zx_pwm_driver);
MODULE_ALIAS("platform:zx-pwm");
MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
MODULE_DESCRIPTION("ZTE ZX PWM Driver");
MODULE_LICENSE("GPL v2");
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