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authorLinus Torvalds <torvalds@linux-foundation.org>2012-08-22 10:27:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-08-22 10:27:12 -0700
commitfec3c03fb07ac2acae03199fa7472a29a0d9b49d (patch)
treed21d660aa91772a5067f2daf24b1f14ebce76176 /drivers
parentf753c4ec151c5c385fa0508a29aa793dee966325 (diff)
parentb817bf5c72774556345a9043c6b0c497cdcb7295 (diff)
downloadlwn-fec3c03fb07ac2acae03199fa7472a29a0d9b49d.tar.gz
lwn-fec3c03fb07ac2acae03199fa7472a29a0d9b49d.zip
Merge tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm
Pull pwm fixes from Thierry Reding: "These patches fix the Samsung PWM driver and perform some minor cleanups like fixing checkpatch and sparse warnings. Two redundant error messages are removed and the Kconfig help text for the PWM subsystem is made more descriptive." * tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm: pwm: Improve Kconfig help text pwm: core: Fix coding style issues pwm: vt8500: Fix coding style issue pwm: Remove a redundant error message when devm_request_and_ioremap fails pwm: samsung: add missing device pointer to struct pwm_chip pwm: Add missing static storage class specifiers in core.c file
Diffstat (limited to 'drivers')
-rw-r--r--drivers/pwm/Kconfig31
-rw-r--r--drivers/pwm/core.c12
-rw-r--r--drivers/pwm/pwm-samsung.c1
-rw-r--r--drivers/pwm/pwm-tegra.c4
-rw-r--r--drivers/pwm/pwm-tiecap.c4
-rw-r--r--drivers/pwm/pwm-tiehrpwm.c4
-rw-r--r--drivers/pwm/pwm-vt8500.c2
7 files changed, 36 insertions, 22 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 8fc3808d7a3e..90c5c7357a50 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -1,12 +1,31 @@
menuconfig PWM
- bool "PWM Support"
+ bool "Pulse-Width Modulation (PWM) Support"
depends on !MACH_JZ4740 && !PUV3_PWM
help
- This enables PWM support through the generic PWM framework.
- You only need to enable this, if you also want to enable
- one or more of the PWM drivers below.
-
- If unsure, say N.
+ Generic Pulse-Width Modulation (PWM) support.
+
+ In Pulse-Width Modulation, a variation of the width of pulses
+ in a rectangular pulse signal is used as a means to alter the
+ average power of the signal. Applications include efficient
+ power delivery and voltage regulation. In computer systems,
+ PWMs are commonly used to control fans or the brightness of
+ display backlights.
+
+ This framework provides a generic interface to PWM devices
+ within the Linux kernel. On the driver side it provides an API
+ to register and unregister a PWM chip, an abstraction of a PWM
+ controller, that supports one or more PWM devices. Client
+ drivers can request PWM devices and use the generic framework
+ to configure as well as enable and disable them.
+
+ This generic framework replaces the legacy PWM framework which
+ allows only a single driver implementing the required API. Not
+ all legacy implementations have been ported to the framework
+ yet. The framework provides an API that is backward compatible
+ with the legacy framework so that existing client drivers
+ continue to work as expected.
+
+ If unsure, say no.
if PWM
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index ecb76909e946..c6e05078d3ad 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -129,8 +129,8 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label)
return 0;
}
-static struct pwm_device *of_pwm_simple_xlate(struct pwm_chip *pc,
- const struct of_phandle_args *args)
+static struct pwm_device *
+of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
{
struct pwm_device *pwm;
@@ -149,7 +149,7 @@ static struct pwm_device *of_pwm_simple_xlate(struct pwm_chip *pc,
return pwm;
}
-void of_pwmchip_add(struct pwm_chip *chip)
+static void of_pwmchip_add(struct pwm_chip *chip)
{
if (!chip->dev || !chip->dev->of_node)
return;
@@ -162,7 +162,7 @@ void of_pwmchip_add(struct pwm_chip *chip)
of_node_get(chip->dev->of_node);
}
-void of_pwmchip_remove(struct pwm_chip *chip)
+static void of_pwmchip_remove(struct pwm_chip *chip)
{
if (chip->dev && chip->dev->of_node)
of_node_put(chip->dev->of_node);
@@ -527,7 +527,7 @@ void __init pwm_add_table(struct pwm_lookup *table, size_t num)
struct pwm_device *pwm_get(struct device *dev, const char *con_id)
{
struct pwm_device *pwm = ERR_PTR(-EPROBE_DEFER);
- const char *dev_id = dev ? dev_name(dev): NULL;
+ const char *dev_id = dev ? dev_name(dev) : NULL;
struct pwm_chip *chip = NULL;
unsigned int index = 0;
unsigned int best = 0;
@@ -609,7 +609,7 @@ void pwm_put(struct pwm_device *pwm)
mutex_lock(&pwm_lock);
if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) {
- pr_warning("PWM device already freed\n");
+ pr_warn("PWM device already freed\n");
goto out;
}
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
index d10386528c9c..e5187c0ade9f 100644
--- a/drivers/pwm/pwm-samsung.c
+++ b/drivers/pwm/pwm-samsung.c
@@ -225,6 +225,7 @@ static int s3c_pwm_probe(struct platform_device *pdev)
/* calculate base of control bits in TCON */
s3c->tcon_base = id == 0 ? 0 : (id * 4) + 4;
+ s3c->chip.dev = &pdev->dev;
s3c->chip.ops = &s3c_pwm_ops;
s3c->chip.base = -1;
s3c->chip.npwm = 1;
diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
index 02ce18d5e49a..057465e0553c 100644
--- a/drivers/pwm/pwm-tegra.c
+++ b/drivers/pwm/pwm-tegra.c
@@ -187,10 +187,8 @@ static int tegra_pwm_probe(struct platform_device *pdev)
}
pwm->mmio_base = devm_request_and_ioremap(&pdev->dev, r);
- if (!pwm->mmio_base) {
- dev_err(&pdev->dev, "failed to ioremap() region\n");
+ if (!pwm->mmio_base)
return -EADDRNOTAVAIL;
- }
platform_set_drvdata(pdev, pwm);
diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c
index 3c2ad284ee3e..0b66d0f25922 100644
--- a/drivers/pwm/pwm-tiecap.c
+++ b/drivers/pwm/pwm-tiecap.c
@@ -192,10 +192,8 @@ static int __devinit ecap_pwm_probe(struct platform_device *pdev)
}
pc->mmio_base = devm_request_and_ioremap(&pdev->dev, r);
- if (!pc->mmio_base) {
- dev_err(&pdev->dev, "failed to ioremap() registers\n");
+ if (!pc->mmio_base)
return -EADDRNOTAVAIL;
- }
ret = pwmchip_add(&pc->chip);
if (ret < 0) {
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index 010d232cb0c8..c3756d1be194 100644
--- a/drivers/pwm/pwm-tiehrpwm.c
+++ b/drivers/pwm/pwm-tiehrpwm.c
@@ -371,10 +371,8 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)
}
pc->mmio_base = devm_request_and_ioremap(&pdev->dev, r);
- if (!pc->mmio_base) {
- dev_err(&pdev->dev, "failed to ioremap() registers\n");
+ if (!pc->mmio_base)
return -EADDRNOTAVAIL;
- }
ret = pwmchip_add(&pc->chip);
if (ret < 0) {
diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
index 548021439f0c..ad14389b7144 100644
--- a/drivers/pwm/pwm-vt8500.c
+++ b/drivers/pwm/pwm-vt8500.c
@@ -41,7 +41,7 @@ static inline void pwm_busy_wait(void __iomem *reg, u8 bitmask)
cpu_relax();
if (unlikely(!loops))
- pr_warning("Waiting for status bits 0x%x to clear timed out\n",
+ pr_warn("Waiting for status bits 0x%x to clear timed out\n",
bitmask);
}