This driver adds functionality to the tps65911 chip driver.
Two of the comparators are configurable by software and measures
VCCS voltage to detect high or low voltage scenarios.
Signed-off-by: Jorge Eduardo Candelaria <[email protected]>
---
drivers/mfd/Kconfig | 7 ++
drivers/mfd/Makefile | 1 +
drivers/mfd/tps65911-comparator.c | 196 +++++++++++++++++++++++++++++++++++++
include/linux/mfd/tps65910.h | 4 +
4 files changed, 208 insertions(+), 0 deletions(-)
create mode 100644 drivers/mfd/tps65911-comparator.c
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 65930a7..7d09045 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -679,6 +679,13 @@ config MFD_TPS65910
if you say yes here you get support for the TPS65910 series of
Power Management chips.
+config PS65911_COMPARATOR
+ tristate "TPS65911 Comparator"
+ depends on MFD_TPS65910
+ help
+ if you say yes here you get support for the TPS65910 comparator
+ module.
+
endif # MFD_SUPPORT
menu "Multimedia Capabilities Port drivers"
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index c771eed..7ae4e2a 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -89,3 +89,4 @@ obj-$(CONFIG_MFD_WL1273_CORE) += wl1273-core.o
obj-$(CONFIG_MFD_CS5535) += cs5535-mfd.o
obj-$(CONFIG_MFD_OMAP_USB_HOST) += omap-usb-host.o
obj-$(CONFIG_MFD_TPS65910) += tps65910.o tps65910-gpio.o tps65910-irq.o
+obj-$(CONFIG_TPS65911_COMP) += tps65911-comparator.o
diff --git a/drivers/mfd/tps65911-comparator.c b/drivers/mfd/tps65911-comparator.c
new file mode 100644
index 0000000..cd2d5f8
--- /dev/null
+++ b/drivers/mfd/tps65911-comparator.c
@@ -0,0 +1,196 @@
+/*
+ * tps65910.c -- TI TPS6591x
+ *
+ * Copyright 2010 Texas Instruments Inc.
+ *
+ * Author: Jorge Eduardo Candelaria <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/debugfs.h>
+#include <linux/gpio.h>
+#include <linux/mfd/tps65910.h>
+
+#define COMP 0
+#define COMP1 1
+#define COMP2 2
+
+/* Comparator 1 voltage selection table in milivolts */
+static const u16 COMP1_VSEL_TABLE[] = {
+ 0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
+ 2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
+ 3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
+ 3500,
+};
+
+/* Comparator 2 voltage selection table in milivolts */
+static const u16 COMP2_VSEL_TABLE[] = {
+ 0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
+ 2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
+ 3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
+ 3500,
+};
+
+struct comparator {
+ const char *name;
+ int reg;
+ int uV_max;
+ const u16 *vsel_table;
+};
+
+static struct comparator tps_comparators[] = {
+ {
+ .name = "COMP1",
+ .reg = TPS65911_VMBCH,
+ .uV_max = 3500,
+ .vsel_table = COMP1_VSEL_TABLE,
+ },
+ {
+ .name = "COMP2",
+ .reg = TPS65911_VMBCH2,
+ .uV_max = 3500,
+ .vsel_table = COMP2_VSEL_TABLE,
+ },
+};
+
+static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)
+{
+ struct comparator tps_comp = tps_comparators[id];
+ int curr_voltage = 0;
+ int ret;
+ u8 index = 0, val;
+
+ if (id == COMP)
+ return 0;
+
+ while (curr_voltage < tps_comp.uV_max) {
+ curr_voltage = tps_comp.vsel_table[index];
+ if (curr_voltage >= voltage)
+ break;
+ else if (curr_voltage < voltage)
+ index ++;
+ }
+
+ if (curr_voltage > tps_comp.uV_max)
+ return -EINVAL;
+
+ val = index << 1;
+ ret = tps65910->write(tps65910, tps_comp.reg, 1, &val);
+
+ return ret;
+}
+
+static int comp_threshold_get(struct tps65910 *tps65910, int id)
+{
+ struct comparator tps_comp = tps_comparators[id];
+ int ret;
+ u8 val;
+
+ if (id == COMP)
+ return 0;
+
+ ret = tps65910->read(tps65910, tps_comp.reg, 1, &val);
+ if (ret < 0)
+ return ret;
+
+ val >>= 1;
+ return tps_comp.vsel_table[val];
+}
+
+static ssize_t comp_threshold_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tps65910 *tps65910 = dev_get_drvdata(dev->parent);
+ struct attribute comp_attr = attr->attr;
+ int id, uVolt;
+
+ if (!strcmp(comp_attr.name, "comp1_threshold"))
+ id = COMP1;
+ else if (!strcmp(comp_attr.name, "comp2_threshold"))
+ id = COMP2;
+ else
+ return -EINVAL;
+
+ uVolt = comp_threshold_get(tps65910, id);
+
+ return sprintf(buf, "%d\n", uVolt);
+}
+
+static DEVICE_ATTR(comp1_threshold, S_IRUGO, comp_threshold_show, NULL);
+static DEVICE_ATTR(comp2_threshold, S_IRUGO, comp_threshold_show, NULL);
+
+static __devinit int tps65911_comparator_probe(struct platform_device *pdev)
+{
+ struct tps65910 *tps65910 = dev_get_drvdata(pdev->dev.parent);
+ struct tps65910_platform_data *pdata = dev_get_platdata(tps65910->dev);
+ int ret;
+
+ ret = comp_threshold_set(tps65910, COMP1, pdata->vmbch_threshold);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "cannot set COMP1 threshold\n");
+ return ret;
+ }
+
+ ret = comp_threshold_set(tps65910, COMP2, pdata->vmbch2_threshold);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "cannot set COMP2 theshold\n");
+ return ret;
+ }
+
+ /* Create sysfs entry */
+ ret = device_create_file(&pdev->dev, &dev_attr_comp1_threshold);
+ if (ret < 0)
+ dev_err(&pdev->dev, "failed to add COMP1 sysfs file\n");
+
+ ret = device_create_file(&pdev->dev, &dev_attr_comp2_threshold);
+ if (ret < 0)
+ dev_err(&pdev->dev, "failed to add COMP2 sysfs file\n");
+
+ return ret;
+}
+
+static __devexit int tps65911_comparator_remove(struct platform_device *pdev)
+{
+ struct tps65910 *tps65910;
+
+ tps65910 = dev_get_drvdata(pdev->dev.parent);
+
+ return 0;
+}
+
+static struct platform_driver tps65911_comparator_driver = {
+ .driver = {
+ .name = "tps65911-comparator",
+ .owner = THIS_MODULE,
+ },
+ .probe = tps65911_comparator_probe,
+ .remove = __devexit_p(tps65911_comparator_remove),
+};
+
+static int __init tps65911_comparator_init(void)
+{
+ return platform_driver_register(&tps65911_comparator_driver);
+}
+subsys_initcall(tps65911_comparator_init);
+
+static void __exit tps65911_comparator_exit(void)
+{
+ platform_driver_unregister(&tps65911_comparator_driver);
+}
+module_exit(tps65911_comparator_exit);
+
+MODULE_AUTHOR("Jorge Eduardo Candelaria <[email protected]>");
+MODULE_DESCRIPTION("TPS65911 comparator driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:tps65911-comparator");
diff --git a/include/linux/mfd/tps65910.h b/include/linux/mfd/tps65910.h
index 5f77006..8bb85b9 100644
--- a/include/linux/mfd/tps65910.h
+++ b/include/linux/mfd/tps65910.h
@@ -121,6 +121,8 @@
#define TPS65911_LDO6 0x35
#define TPS65911_LDO4 0x36
#define TPS65911_LDO3 0x37
+#define TPS65911_VMBCH 0x6A
+#define TPS65911_VMBCH2 0x6B
/*
* List of register bitfields for component TPS65910
@@ -746,6 +748,8 @@ struct tps65910_board {
int gpio_base;
int irq;
int irq_base;
+ int vmbch_threshold;
+ int vmbch2_threshold;
struct regulator_init_data *tps65910_pmic_init_data;
};
--
1.7.1
On Tue, May 03, 2011 at 11:19:07AM -0500, Jorge Eduardo Candelaria wrote:
> +/* Comparator 1 voltage selection table in milivolts */
> +static const u16 COMP1_VSEL_TABLE[] = {
> + 0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
> + 2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
> + 3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
> + 3500,
> +};
> +
> +/* Comparator 2 voltage selection table in milivolts */
> +static const u16 COMP2_VSEL_TABLE[] = {
> + 0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
> + 2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
> + 3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
> + 3500,
> +};
These look remarkably similar...
> +static DEVICE_ATTR(comp1_threshold, S_IRUGO, comp_threshold_show, NULL);
> +static DEVICE_ATTR(comp2_threshold, S_IRUGO, comp_threshold_show, NULL);
We should really have a proper API for this, it's a pretty common
feature on devices with an auxilliary ADC of some kind.