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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 17:29:55 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 17:29:55 -0700
commitf0c1bc95a108b36677dde6c9d96a5bb810a05b75 (patch)
tree335c33469407d0ebda5670dabb49c6ecad64263e /drivers/video/backlight/sky81452-backlight.c
parent1dcf58d6e6e6eb7ec10e9abc56887b040205b06f (diff)
parente554a99ee8d09132e80dc467433c9a4df9054645 (diff)
downloadlinux-f0c1bc95a108b36677dde6c9d96a5bb810a05b75.tar.gz
linux-f0c1bc95a108b36677dde6c9d96a5bb810a05b75.tar.xz
Merge tag 'mfd-for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones: "Changes to existing drivers: - Rename child driver [axp288_battery => axp288_fuel_gauge]; axp20x - Rename child driver [max77693-flash => max77693-led]; max77693 - Error handling fixes; intel_soc_pmic - GPIO tweaking; intel_soc_pmic - Remove non-DT code; vexpress-sysreg, tc3589x - Remove unused/legacy code; ti_am335x_tscadc, rts5249, rtsx_gops, rtsx_pcr, rtc-s5m, sec-core, max77693, menelaus, wm5102-tables - Trivial fixups; rtsx_pci, da9150-core, sec-core, max7769, max77693, mc13xxx-core, dln2, hi6421-pmic-core, rk808, twl4030-power, lpc_ich, menelaus, twl6040 - Update register/address values; rts5227, rts5249 - DT and/or binding document fixups; arizona, da9150, mt6397, axp20x, qcom-rpm, qcom-spmi-pmic - Couple of trivial core Kconfig fixups - Remove use of seq_printf return value; ab8500-debugfs - Remove __exit markups; menelaus, tps65010 - Fix platform-device name collisions; mfd-core New drivers/supported devices: - Add support for wm8280/wm8281 into arizona - Add support for COMe-cBL6 into kempld-core - Add support for rts524a and rts525a into rts5249 - Add support for ipq8064 into qcom_rpm - Add support for extcon into axp20x - New MediaTek MT6397 PMIC driver - New Maxim MAX77843 PMIC dirver - New Intel Quark X1000 I2C-GPIO driver - New Skyworks SKY81452 driver" * tag 'mfd-for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (76 commits) mfd: sec: Fix RTC alarm interrupt number on S2MPS11 mfd: wm5102: Remove registers for output 3R from readable list mfd: tps65010: Remove incorrect __exit markups mfd: devicetree: bindings: Add Qualcomm RPM regulator subnodes mfd: axp20x: Add support for extcon cell mfd: lpc_ich: Sort IDs mfd: twl6040: Remove wrong and unneeded "platform:twl6040" modalias mfd: qcom-spmi-pmic: Add specific compatible strings for Qualcomm's SPMI PMIC's mfd: axp20x: Fix duplicate const for model names mfd: menelaus: Use macro for magic number mfd: menelaus: Drop support for SW controller VCORE mfd: menelaus: Delete omap_has_menelaus mfd: arizona: Correct type of gpio_defaults mfd: lpc_ich: Sort IDs mfd: Fix a typo in Kconfig mfd: qcom_rpm: Add support for IPQ8064 mfd: devicetree: qcom_rpm: Document IPQ8064 resources mfd: core: Fix platform-device name collisions mfd: intel_quark_i2c_gpio: Don't crash if !DMI dt-bindings: Add vendor-prefix for X-Powers ...
Diffstat (limited to 'drivers/video/backlight/sky81452-backlight.c')
-rw-r--r--drivers/video/backlight/sky81452-backlight.c353
1 files changed, 353 insertions, 0 deletions
diff --git a/drivers/video/backlight/sky81452-backlight.c b/drivers/video/backlight/sky81452-backlight.c
new file mode 100644
index 000000000000..052fa1bac03d
--- /dev/null
+++ b/drivers/video/backlight/sky81452-backlight.c
@@ -0,0 +1,353 @@
+/*
+ * sky81452-backlight.c SKY81452 backlight driver
+ *
+ * Copyright 2014 Skyworks Solutions Inc.
+ * Author : Gyungoh Yoo <jack.yoo@skyworksinc.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/platform_data/sky81452-backlight.h>
+#include <linux/slab.h>
+
+/* registers */
+#define SKY81452_REG0 0x00
+#define SKY81452_REG1 0x01
+#define SKY81452_REG2 0x02
+#define SKY81452_REG4 0x04
+#define SKY81452_REG5 0x05
+
+/* bit mask */
+#define SKY81452_CS 0xFF
+#define SKY81452_EN 0x3F
+#define SKY81452_IGPW 0x20
+#define SKY81452_PWMMD 0x10
+#define SKY81452_PHASE 0x08
+#define SKY81452_ILIM 0x04
+#define SKY81452_VSHRT 0x03
+#define SKY81452_OCP 0x80
+#define SKY81452_OTMP 0x40
+#define SKY81452_SHRT 0x3F
+#define SKY81452_OPN 0x3F
+
+#define SKY81452_DEFAULT_NAME "lcd-backlight"
+#define SKY81452_MAX_BRIGHTNESS (SKY81452_CS + 1)
+
+#define CTZ(b) __builtin_ctz(b)
+
+static int sky81452_bl_update_status(struct backlight_device *bd)
+{
+ const struct sky81452_bl_platform_data *pdata =
+ dev_get_platdata(bd->dev.parent);
+ const unsigned int brightness = (unsigned int)bd->props.brightness;
+ struct regmap *regmap = bl_get_data(bd);
+ int ret;
+
+ if (brightness > 0) {
+ ret = regmap_write(regmap, SKY81452_REG0, brightness - 1);
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ return regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN,
+ pdata->enable << CTZ(SKY81452_EN));
+ }
+
+ return regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN, 0);
+}
+
+static const struct backlight_ops sky81452_bl_ops = {
+ .update_status = sky81452_bl_update_status,
+};
+
+static ssize_t sky81452_bl_store_enable(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct regmap *regmap = bl_get_data(to_backlight_device(dev));
+ unsigned long value;
+ int ret;
+
+ ret = kstrtoul(buf, 16, &value);
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ ret = regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN,
+ value << CTZ(SKY81452_EN));
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ return count;
+}
+
+static ssize_t sky81452_bl_show_open_short(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regmap *regmap = bl_get_data(to_backlight_device(dev));
+ unsigned int reg, value = 0;
+ char tmp[3];
+ int i, ret;
+
+ reg = !strcmp(attr->attr.name, "open") ? SKY81452_REG5 : SKY81452_REG4;
+ ret = regmap_read(regmap, reg, &value);
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ if (value & SKY81452_SHRT) {
+ *buf = 0;
+ for (i = 0; i < 6; i++) {
+ if (value & 0x01) {
+ sprintf(tmp, "%d ", i + 1);
+ strcat(buf, tmp);
+ }
+ value >>= 1;
+ }
+ strcat(buf, "\n");
+ } else {
+ strcpy(buf, "none\n");
+ }
+
+ return strlen(buf);
+}
+
+static ssize_t sky81452_bl_show_fault(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct regmap *regmap = bl_get_data(to_backlight_device(dev));
+ unsigned int value = 0;
+ int ret;
+
+ ret = regmap_read(regmap, SKY81452_REG4, &value);
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ *buf = 0;
+
+ if (value & SKY81452_OCP)
+ strcat(buf, "over-current ");
+
+ if (value & SKY81452_OTMP)
+ strcat(buf, "over-temperature");
+
+ strcat(buf, "\n");
+ return strlen(buf);
+}
+
+static DEVICE_ATTR(enable, S_IWGRP | S_IWUSR, NULL, sky81452_bl_store_enable);
+static DEVICE_ATTR(open, S_IRUGO, sky81452_bl_show_open_short, NULL);
+static DEVICE_ATTR(short, S_IRUGO, sky81452_bl_show_open_short, NULL);
+static DEVICE_ATTR(fault, S_IRUGO, sky81452_bl_show_fault, NULL);
+
+static struct attribute *sky81452_bl_attribute[] = {
+ &dev_attr_enable.attr,
+ &dev_attr_open.attr,
+ &dev_attr_short.attr,
+ &dev_attr_fault.attr,
+ NULL
+};
+
+static const struct attribute_group sky81452_bl_attr_group = {
+ .attrs = sky81452_bl_attribute,
+};
+
+#ifdef CONFIG_OF
+static struct sky81452_bl_platform_data *sky81452_bl_parse_dt(
+ struct device *dev)
+{
+ struct device_node *np = of_node_get(dev->of_node);
+ struct sky81452_bl_platform_data *pdata;
+ int num_entry;
+ unsigned int sources[6];
+ int ret;
+
+ if (!np) {
+ dev_err(dev, "backlight node not found.\n");
+ return ERR_PTR(-ENODATA);
+ }
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ of_node_put(np);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ of_property_read_string(np, "name", &pdata->name);
+ pdata->ignore_pwm = of_property_read_bool(np, "skyworks,ignore-pwm");
+ pdata->dpwm_mode = of_property_read_bool(np, "skyworks,dpwm-mode");
+ pdata->phase_shift = of_property_read_bool(np, "skyworks,phase-shift");
+ pdata->gpio_enable = of_get_gpio(np, 0);
+
+ ret = of_property_count_u32_elems(np, "led-sources");
+ if (IS_ERR_VALUE(ret)) {
+ pdata->enable = SKY81452_EN >> CTZ(SKY81452_EN);
+ } else {
+ num_entry = ret;
+ if (num_entry > 6)
+ num_entry = 6;
+
+ ret = of_property_read_u32_array(np, "led-sources", sources,
+ num_entry);
+ if (IS_ERR_VALUE(ret)) {
+ dev_err(dev, "led-sources node is invalid.\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ pdata->enable = 0;
+ while (--num_entry)
+ pdata->enable |= (1 << sources[num_entry]);
+ }
+
+ ret = of_property_read_u32(np,
+ "skyworks,short-detection-threshold-volt",
+ &pdata->short_detection_threshold);
+ if (IS_ERR_VALUE(ret))
+ pdata->short_detection_threshold = 7;
+
+ ret = of_property_read_u32(np, "skyworks,current-limit-mA",
+ &pdata->boost_current_limit);
+ if (IS_ERR_VALUE(ret))
+ pdata->boost_current_limit = 2750;
+
+ of_node_put(np);
+ return pdata;
+}
+#else
+static struct sky81452_bl_platform_data *sky81452_bl_parse_dt(
+ struct device *dev)
+{
+ return ERR_PTR(-EINVAL);
+}
+#endif
+
+static int sky81452_bl_init_device(struct regmap *regmap,
+ struct sky81452_bl_platform_data *pdata)
+{
+ unsigned int value;
+
+ value = pdata->ignore_pwm ? SKY81452_IGPW : 0;
+ value |= pdata->dpwm_mode ? SKY81452_PWMMD : 0;
+ value |= pdata->phase_shift ? 0 : SKY81452_PHASE;
+
+ if (pdata->boost_current_limit == 2300)
+ value |= SKY81452_ILIM;
+ else if (pdata->boost_current_limit != 2750)
+ return -EINVAL;
+
+ if (pdata->short_detection_threshold < 4 ||
+ pdata->short_detection_threshold > 7)
+ return -EINVAL;
+ value |= (7 - pdata->short_detection_threshold) << CTZ(SKY81452_VSHRT);
+
+ return regmap_write(regmap, SKY81452_REG2, value);
+}
+
+static int sky81452_bl_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct regmap *regmap = dev_get_drvdata(dev->parent);
+ struct sky81452_bl_platform_data *pdata = dev_get_platdata(dev);
+ struct backlight_device *bd;
+ struct backlight_properties props;
+ const char *name;
+ int ret;
+
+ if (!pdata) {
+ pdata = sky81452_bl_parse_dt(dev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+ }
+
+ if (gpio_is_valid(pdata->gpio_enable)) {
+ ret = devm_gpio_request_one(dev, pdata->gpio_enable,
+ GPIOF_OUT_INIT_HIGH, "sky81452-en");
+ if (IS_ERR_VALUE(ret)) {
+ dev_err(dev, "failed to request GPIO. err=%d\n", ret);
+ return ret;
+ }
+ }
+
+ ret = sky81452_bl_init_device(regmap, pdata);
+ if (IS_ERR_VALUE(ret)) {
+ dev_err(dev, "failed to initialize. err=%d\n", ret);
+ return ret;
+ }
+
+ memset(&props, 0, sizeof(props));
+ props.max_brightness = SKY81452_MAX_BRIGHTNESS,
+ name = pdata->name ? pdata->name : SKY81452_DEFAULT_NAME;
+ bd = devm_backlight_device_register(dev, name, dev, regmap,
+ &sky81452_bl_ops, &props);
+ if (IS_ERR(bd)) {
+ dev_err(dev, "failed to register. err=%ld\n", PTR_ERR(bd));
+ return PTR_ERR(bd);
+ }
+
+ platform_set_drvdata(pdev, bd);
+
+ ret = sysfs_create_group(&bd->dev.kobj, &sky81452_bl_attr_group);
+ if (IS_ERR_VALUE(ret)) {
+ dev_err(dev, "failed to create attribute. err=%d\n", ret);
+ return ret;
+ }
+
+ return ret;
+}
+
+static int sky81452_bl_remove(struct platform_device *pdev)
+{
+ const struct sky81452_bl_platform_data *pdata =
+ dev_get_platdata(&pdev->dev);
+ struct backlight_device *bd = platform_get_drvdata(pdev);
+
+ sysfs_remove_group(&bd->dev.kobj, &sky81452_bl_attr_group);
+
+ bd->props.power = FB_BLANK_UNBLANK;
+ bd->props.brightness = 0;
+ backlight_update_status(bd);
+
+ if (gpio_is_valid(pdata->gpio_enable))
+ gpio_set_value_cansleep(pdata->gpio_enable, 0);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id sky81452_bl_of_match[] = {
+ { .compatible = "skyworks,sky81452-backlight", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sky81452_bl_of_match);
+#endif
+
+static struct platform_driver sky81452_bl_driver = {
+ .driver = {
+ .name = "sky81452-backlight",
+ .of_match_table = of_match_ptr(sky81452_bl_of_match),
+ },
+ .probe = sky81452_bl_probe,
+ .remove = sky81452_bl_remove,
+};
+
+module_platform_driver(sky81452_bl_driver);
+
+MODULE_DESCRIPTION("Skyworks SKY81452 backlight driver");
+MODULE_AUTHOR("Gyungoh Yoo <jack.yoo@skyworksinc.com>");
+MODULE_LICENSE("GPL v2");