[RFC PATCH 09/11] ARM: OMAP4+: thermal: introduce bandgap temperature sensor
Konstantin Baydarov
kbaidarov at dev.rtsoft.ru
Fri May 25 12:39:09 EDT 2012
Hi.
On 05/25/2012 12:25 PM, Eduardo Valentin wrote:
> In the System Control Module, OMAP supplies a voltage reference
> and a temperature sensor feature that are gathered in the band
> gap voltage and temperature sensor (VBGAPTS) module. The band
> gap provides current and voltage reference for its internal
> circuits and other analog IP blocks. The analog-to-digital
> converter (ADC) produces an output value that is proportional
> to the silicon temperature.
>
> This patch provides a platform driver which expose this feature.
> It is moduled as a MFD child of the System Control Module core
> MFD driver.
>
> This driver provides only APIs to access the device properties,
> like temperature, thresholds and update rate.
>
> Signed-off-by: Eduardo Valentin <eduardo.valentin at ti.com>
> Signed-off-by: Keerthy <j-keerthy at ti.com>
> ---
> .../devicetree/bindings/thermal/omap_bandgap.txt | 27 +
> drivers/thermal/Kconfig | 13 +
> drivers/thermal/Makefile | 4 +-
> drivers/thermal/omap-bandgap.c | 1601 ++++++++++++++++++++
> drivers/thermal/omap-bandgap.h | 63 +
> 5 files changed, 1707 insertions(+), 1 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/thermal/omap_bandgap.txt
> create mode 100644 drivers/thermal/omap-bandgap.c
> create mode 100644 drivers/thermal/omap-bandgap.h
>
>
Add private spin lock in omap-bandgap driver to prevent blocking of
control module general registers access.
I wasn't able to test - I have panda 4430 board.
TODO:
Prevent over-usage of spin_lock/spin_unlock for sequential calls of
bg_writel().
Signed-off-by: Konstantin Baydarov <kbaidarov at dev.rtsoft.ru>
Index: omap-thermal/drivers/mfd/omap-control-core.c
===================================================================
--- omap-thermal.orig/drivers/mfd/omap-control-core.c
+++ omap-thermal/drivers/mfd/omap-control-core.c
@@ -67,6 +67,19 @@ EXPORT_SYMBOL_GPL(omap_control_readl);
int omap_control_writel(struct device *dev, u32 val, u32 reg)
{
struct omap_control *omap_control = dev_get_drvdata(dev);
+
+ if (!omap_control)
+ return -EINVAL;
+
+ writel(val, omap_control->base + reg);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(omap_control_writel);
+
+int omap_control_lock_writel(struct device *dev, u32 val, u32 reg)
+{
+ struct omap_control *omap_control = dev_get_drvdata(dev);
unsigned long flags;
if (!omap_control)
@@ -78,7 +91,7 @@ int omap_control_writel(struct device *d
return 0;
}
-EXPORT_SYMBOL_GPL(omap_control_writel);
+EXPORT_SYMBOL_GPL(omap_control_lock_writel);
/**
* omap_control_get: returns the control module device pinter
@@ -136,6 +149,9 @@ static int __devinit omap_control_probe(
struct device_node *np = dev->of_node;
struct omap_control *omap_control;
+ printk("\n\t\t **** omap_control_probe(): enter ");
+ dump_stack();
+
omap_control = devm_kzalloc(dev, sizeof(*omap_control), GFP_KERNEL);
if (!omap_control) {
dev_err(dev, "not enough memory for omap_control\n");
Index: omap-thermal/drivers/thermal/omap-bandgap.c
===================================================================
--- omap-thermal.orig/drivers/thermal/omap-bandgap.c
+++ omap-thermal/drivers/thermal/omap-bandgap.c
@@ -154,6 +154,7 @@ struct temp_sensor_registers {
u32 status_cold_mask;
u32 bgap_efuse;
+ spinlock_t bg_reg_lock;
};
/**
@@ -579,6 +580,17 @@ omap5430_adc_to_temp[OMAP5430_ADC_END_VA
124600, 124900, 125000, 125000, 125000, 125000,
};
+static int bg_writel(struct device *dev, u32 val, u32 reg, spinlock_t *lock)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(lock, flags);
+ ret = omap_control_writel(dev, val, reg);
+ spin_unlock_irqrestore(lock, flags);
+ return ret;
+}
+
static irqreturn_t talert_irq_handler(int irq, void *data)
{
struct omap_bandgap *bg_ptr = data;
@@ -615,7 +627,7 @@ static irqreturn_t talert_irq_handler(in
ctrl |= tsr->mask_hot_mask;
}
- r |= omap_control_writel(cdev, ctrl, tsr->bgap_mask_ctrl);
+ r |= bg_writel(cdev, ctrl, tsr->bgap_mask_ctrl, &tsr->bg_reg_lock);
if (r) {
dev_err(bg_ptr->dev, "failed to ack talert interrupt\n");
@@ -705,7 +717,7 @@ static int temp_sensor_unmask_interrupts
reg_val |= tsr->mask_cold_mask;
else
reg_val &= ~tsr->mask_cold_mask;
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_mask_ctrl);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_mask_ctrl, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to unmask interrupts\n");
@@ -751,14 +763,14 @@ int temp_sensor_configure_thot(struct om
/* write the new t_cold value */
reg_val = thresh_val & (~tsr->threshold_tcold_mask);
reg_val |= cold << __ffs(tsr->threshold_tcold_mask);
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_threshold, &tsr->bg_reg_lock);
thresh_val = reg_val;
}
/* write the new t_hot value */
reg_val = thresh_val & ~tsr->threshold_thot_mask;
reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask));
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_threshold, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram thot threshold\n");
return -EIO;
@@ -782,7 +794,7 @@ int temp_sensor_init_talert_thresholds(s
/* write the new t_cold value */
reg_val = thresh_val & ~tsr->threshold_tcold_mask;
reg_val |= (t_cold << __ffs(tsr->threshold_tcold_mask));
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_threshold, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram tcold threshold\n");
return -EIO;
@@ -793,7 +805,7 @@ int temp_sensor_init_talert_thresholds(s
/* write the new t_hot value */
reg_val = thresh_val & ~tsr->threshold_thot_mask;
reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask));
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_threshold, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram thot threshold\n");
return -EIO;
@@ -802,7 +814,7 @@ int temp_sensor_init_talert_thresholds(s
err = omap_control_readl(cdev, tsr->bgap_mask_ctrl, ®_val);
reg_val |= tsr->mask_hot_mask;
reg_val |= tsr->mask_cold_mask;
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_mask_ctrl);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_mask_ctrl, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram thot threshold\n");
return -EIO;
@@ -833,14 +845,14 @@ int temp_sensor_configure_tcold(struct o
/* write the new t_hot value */
reg_val = thresh_val & (~tsr->threshold_thot_mask);
reg_val |= hot << __ffs(tsr->threshold_thot_mask);
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_threshold, &tsr->bg_reg_lock);
thresh_val = reg_val;
}
/* write the new t_cold value */
reg_val = thresh_val & ~tsr->threshold_tcold_mask;
reg_val |= (t_cold << __ffs(tsr->threshold_tcold_mask));
- err |= omap_control_writel(cdev, reg_val, tsr->bgap_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->bgap_threshold, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram tcold threshold\n");
return -EIO;
@@ -861,7 +873,7 @@ static int temp_sensor_configure_tshut_h
err = omap_control_readl(cdev, tsr->tshut_threshold, ®_val);
reg_val &= ~tsr->tshut_hot_mask;
reg_val |= tshut_hot << __ffs(tsr->tshut_hot_mask);
- err |= omap_control_writel(cdev, reg_val, tsr->tshut_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->tshut_threshold, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram tshut thot\n");
return -EIO;
@@ -882,7 +894,7 @@ static int temp_sensor_configure_tshut_c
err = omap_control_readl(cdev, tsr->tshut_threshold, ®_val);
reg_val &= ~tsr->tshut_cold_mask;
reg_val |= tshut_cold << __ffs(tsr->tshut_cold_mask);
- err |= omap_control_writel(cdev, reg_val, tsr->tshut_threshold);
+ err |= bg_writel(cdev, reg_val, tsr->tshut_threshold, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram tshut tcold\n");
return -EIO;
@@ -903,7 +915,7 @@ static int configure_temp_sensor_counter
err = omap_control_readl(cdev, tsr->bgap_counter, &val);
val &= ~tsr->counter_mask;
val |= counter << __ffs(tsr->counter_mask);
- err |= omap_control_writel(cdev, val, tsr->bgap_counter);
+ err |= bg_writel(cdev, val, tsr->bgap_counter, &tsr->bg_reg_lock);
if (err) {
dev_err(bg_ptr->dev, "failed to reprogram tshut tcold\n");
return -EIO;
@@ -1124,7 +1136,7 @@ static int enable_continuous_mode(struct
tsr = bg_ptr->pdata->sensors[i].registers;
r = omap_control_readl(cdev, tsr->bgap_mode_ctrl, &val);
val |= 1 << __ffs(tsr->mode_ctrl_mask);
- r |= omap_control_writel(cdev, val, tsr->bgap_mode_ctrl);
+ r |= bg_writel(cdev, val, tsr->bgap_mode_ctrl, &tsr->bg_reg_lock);
if (r)
dev_err(bg_ptr->dev, "could not save sensor %d\n", i);
}
@@ -1342,6 +1354,9 @@ int __devinit omap_bandgap_probe(struct
u32 val;
tsr = bg_ptr->pdata->sensors[i].registers;
+ /* Initialize register lock */
+ spin_lock_init(&tsr->bg_reg_lock);
+
/*
* check if the efuse has a non-zero value if not
* it is an untrimmed sample and the temperatures
@@ -1482,12 +1497,12 @@ omap_bandgap_force_single_read(struct om
/* Select single conversion mode */
err = omap_control_readl(cdev, tsr->bgap_mode_ctrl, &temp);
temp &= ~(1 << __ffs(tsr->mode_ctrl_mask));
- omap_control_writel(cdev, temp, tsr->bgap_mode_ctrl);
+ bg_writel(cdev, temp, tsr->bgap_mode_ctrl, &tsr->bg_reg_lock);
/* Start of Conversion = 1 */
err |= omap_control_readl(cdev, tsr->temp_sensor_ctrl, &temp);
temp |= 1 << __ffs(tsr->bgap_soc_mask);
- omap_control_writel(cdev, temp, tsr->temp_sensor_ctrl);
+ bg_writel(cdev, temp, tsr->temp_sensor_ctrl, &tsr->bg_reg_lock);
/* Wait until DTEMP is updated */
err |= omap_control_readl(cdev, tsr->temp_sensor_ctrl, &temp);
temp &= (tsr->bgap_dtemp_mask);
@@ -1498,7 +1513,7 @@ omap_bandgap_force_single_read(struct om
/* Start of Conversion = 0 */
err |= omap_control_readl(cdev, tsr->temp_sensor_ctrl, &temp);
temp &= ~(1 << __ffs(tsr->bgap_soc_mask));
- err |= omap_control_writel(cdev, temp, tsr->temp_sensor_ctrl);
+ err |= bg_writel(cdev, temp, tsr->temp_sensor_ctrl, &tsr->bg_reg_lock);
return err ? -EIO : 0;
}
@@ -1519,20 +1534,20 @@ static int omap_bandgap_restore_ctxt(str
err = omap_control_readl(cdev, tsr->bgap_counter, &val);
if (val == 0) {
- err |= omap_control_writel(cdev, rval->bg_threshold,
- tsr->bgap_threshold);
- err |= omap_control_writel(cdev, rval->tshut_threshold,
- tsr->tshut_threshold);
+ err |= bg_writel(cdev, rval->bg_threshold,
+ tsr->bgap_threshold, &tsr->bg_reg_lock);
+ err |= bg_writel(cdev, rval->tshut_threshold,
+ tsr->tshut_threshold, &tsr->bg_reg_lock);
/* Force immediate temperature measurement and update
* of the DTEMP field
*/
omap_bandgap_force_single_read(bg_ptr, i);
- err |= omap_control_writel(cdev, rval->bg_counter,
- tsr->bgap_counter);
- err |= omap_control_writel(cdev, rval->bg_mode_ctrl,
- tsr->bgap_mode_ctrl);
- err |= omap_control_writel(cdev, rval->bg_ctrl,
- tsr->bgap_mask_ctrl);
+ err |= bg_writel(cdev, rval->bg_counter,
+ tsr->bgap_counter, &tsr->bg_reg_lock);
+ err |= bg_writel(cdev, rval->bg_mode_ctrl,
+ tsr->bgap_mode_ctrl, &tsr->bg_reg_lock);
+ err |= bg_writel(cdev, rval->bg_ctrl,
+ tsr->bgap_mask_ctrl, &tsr->bg_reg_lock);
} else {
err |= omap_control_readl(cdev, tsr->temp_sensor_ctrl,
&temp);
@@ -1543,8 +1558,8 @@ static int omap_bandgap_restore_ctxt(str
tsr->bgap_mask_ctrl,
&temp);
temp |= 1 << __ffs(tsr->mode_ctrl_mask);
- err |= omap_control_writel(cdev, temp,
- tsr->bgap_mask_ctrl);
+ err |= bg_writel(cdev, temp,
+ tsr->bgap_mask_ctrl, &tsr->bg_reg_lock);
}
}
if (err)
Index: omap-thermal/drivers/usb/otg/omap4-usb-phy.c
===================================================================
--- omap-thermal.orig/drivers/usb/otg/omap4-usb-phy.c
+++ omap-thermal/drivers/usb/otg/omap4-usb-phy.c
@@ -46,13 +46,13 @@ int omap4_usb_phy_power(struct device *d
if (on) {
ret = omap_control_readl(dev, CONTROL_DEV_CONF, &val);
if (!ret && (val & PHY_PD)) {
- ret = omap_control_writel(dev, ~PHY_PD,
+ ret = omap_control_lock_writel(dev, ~PHY_PD,
CONTROL_DEV_CONF);
/* XXX: add proper documentation for this delay */
mdelay(200);
}
} else {
- ret = omap_control_writel(dev, PHY_PD, CONTROL_DEV_CONF);
+ ret = omap_control_lock_writel(dev, PHY_PD, CONTROL_DEV_CONF);
}
return ret;
@@ -74,7 +74,7 @@ EXPORT_SYMBOL_GPL(omap4_usb_phy_power);
*/
int omap4_usb_phy_mailbox(struct device *dev, u32 val)
{
- return omap_control_writel(dev, val, CONTROL_USBOTGHS_CONTROL);
+ return omap_control_lock_writel(dev, val, CONTROL_USBOTGHS_CONTROL);
}
EXPORT_SYMBOL_GPL(omap4_usb_phy_mailbox);
Index: omap-thermal/include/linux/mfd/omap_control.h
===================================================================
--- omap-thermal.orig/include/linux/mfd/omap_control.h
+++ omap-thermal/include/linux/mfd/omap_control.h
@@ -43,6 +43,7 @@ struct omap_control {
#ifdef CONFIG_MFD_OMAP_CONTROL
extern int omap_control_readl(struct device *dev, u32 reg, u32 *val);
extern int omap_control_writel(struct device *dev, u32 val, u32 reg);
+extern int omap_control_lock_writel(struct device *dev, u32 val, u32 reg);
extern struct device *omap_control_get(void);
extern void omap_control_put(struct device *dev);
#else
@@ -55,6 +56,11 @@ static inline int omap_control_writel(st
{
return 0;
}
+
+static inline int omap_control_lock_writel(struct device *dev, u32 val, u32 reg)
+{
+ return 0;
+}
static inline struct device *omap_control_get(void)
{
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