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authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-19 23:01:26 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-19 23:37:01 +0200
commit2ae782ca839e0ee07de37122ddea362adff2e975 (patch)
treedf6b1a190760f51465122ca4c13492d5ac5984c6 /drivers/pwm/pwm-meson.c
parent0a8ab17689e628c84a666195bfc6ab85d11cf057 (diff)
parent0661b3d6cfd774e28a2e2ba90a3d87479e5c399b (diff)
Merge tag 'v4.9.220' into 4.9-2.3.x-imx
This is the 4.9.220 stable release Conflicts: arch/arm/Kconfig.debug arch/arm/boot/dts/imx7s.dtsi arch/arm/mach-imx/common.h arch/arm/mach-imx/cpuidle-imx6q.c arch/arm/mach-imx/cpuidle-imx6sx.c arch/arm/mach-imx/suspend-imx6.S block/blk-core.c drivers/crypto/caam/caamalg.c drivers/crypto/mxs-dcp.c drivers/dma/imx-sdma.c drivers/gpu/drm/bridge/adv7511/adv7511_drv.c drivers/input/keyboard/imx_keypad.c drivers/input/keyboard/snvs_pwrkey.c drivers/mmc/host/sdhci.c drivers/net/can/flexcan.c drivers/net/ethernet/freescale/fec_main.c drivers/net/phy/phy_device.c drivers/net/wireless/ath/ath10k/pci.c drivers/tty/serial/imx.c drivers/usb/dwc3/gadget.c drivers/usb/host/xhci.c include/linux/blkdev.h include/linux/cpu.h include/linux/platform_data/dma-imx-sdma.h kernel/cpu.c net/wireless/util.c sound/soc/fsl/Kconfig sound/soc/fsl/fsl_esai.c sound/soc/fsl/fsl_sai.c sound/soc/fsl/imx-sgtl5000.c
Diffstat (limited to 'drivers/pwm/pwm-meson.c')
-rw-r--r--drivers/pwm/pwm-meson.c30
1 files changed, 17 insertions, 13 deletions
diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 9d5bd7d5c610..a196439ee14c 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -110,6 +110,10 @@ struct meson_pwm {
const struct meson_pwm_data *data;
void __iomem *base;
u8 inverter_mask;
+ /*
+ * Protects register (write) access to the REG_MISC_AB register
+ * that is shared between the two PWMs.
+ */
spinlock_t lock;
};
@@ -230,6 +234,7 @@ static void meson_pwm_enable(struct meson_pwm *meson,
{
u32 value, clk_shift, clk_enable, enable;
unsigned int offset;
+ unsigned long flags;
switch (id) {
case 0:
@@ -250,6 +255,8 @@ static void meson_pwm_enable(struct meson_pwm *meson,
return;
}
+ spin_lock_irqsave(&meson->lock, flags);
+
value = readl(meson->base + REG_MISC_AB);
value &= ~(MISC_CLK_DIV_MASK << clk_shift);
value |= channel->pre_div << clk_shift;
@@ -262,11 +269,14 @@ static void meson_pwm_enable(struct meson_pwm *meson,
value = readl(meson->base + REG_MISC_AB);
value |= enable;
writel(value, meson->base + REG_MISC_AB);
+
+ spin_unlock_irqrestore(&meson->lock, flags);
}
static void meson_pwm_disable(struct meson_pwm *meson, unsigned int id)
{
u32 value, enable;
+ unsigned long flags;
switch (id) {
case 0:
@@ -281,9 +291,13 @@ static void meson_pwm_disable(struct meson_pwm *meson, unsigned int id)
return;
}
+ spin_lock_irqsave(&meson->lock, flags);
+
value = readl(meson->base + REG_MISC_AB);
value &= ~enable;
writel(value, meson->base + REG_MISC_AB);
+
+ spin_unlock_irqrestore(&meson->lock, flags);
}
static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -291,29 +305,21 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
{
struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
struct meson_pwm *meson = to_meson_pwm(chip);
- unsigned long flags;
int err = 0;
if (!state)
return -EINVAL;
- spin_lock_irqsave(&meson->lock, flags);
-
if (!state->enabled) {
meson_pwm_disable(meson, pwm->hwpwm);
channel->state.enabled = false;
- goto unlock;
+ return 0;
}
if (state->period != channel->state.period ||
state->duty_cycle != channel->state.duty_cycle ||
state->polarity != channel->state.polarity) {
- if (channel->state.enabled) {
- meson_pwm_disable(meson, pwm->hwpwm);
- channel->state.enabled = false;
- }
-
if (state->polarity != channel->state.polarity) {
if (state->polarity == PWM_POLARITY_NORMAL)
meson->inverter_mask |= BIT(pwm->hwpwm);
@@ -324,7 +330,7 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
err = meson_pwm_calc(meson, channel, pwm->hwpwm,
state->duty_cycle, state->period);
if (err < 0)
- goto unlock;
+ return err;
channel->state.polarity = state->polarity;
channel->state.period = state->period;
@@ -336,9 +342,7 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
channel->state.enabled = true;
}
-unlock:
- spin_unlock_irqrestore(&meson->lock, flags);
- return err;
+ return 0;
}
static void meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,