drivers/misc: ROHM BH1780GLI ambient light sensor driver

Add support for ROHM BH1780GLI Ambient light sensor. BH1780 supports I2C interface. Driver supports read/update of power state and read of lux value (through SYSFS). Writing value 3 to power_state enables the sensor and current lux value could be read. Currently this driver follows the same sysfs convention as supported by drivers/misc/isl29003.c. Signed-off-by: Hemanth V <hemanthv@ti.com> Reviewed-by: Daniel Mack <daniel@caiaq.de> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Cc: Jean Delvare <khali@linux-fr.org> Cc: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc: ROHM BH1780GLI ambient light sensor driver
Add support for ROHM BH1780GLI Ambient light sensor. BH1780 supports I2C interface. Driver supports read/update of power state and read of lux value (through SYSFS). Writing value 3 to power_state enables the sensor and current lux value could be read. Currently this driver follows the same sysfs convention as supported by drivers/misc/isl29003.c. Signed-off-by: Hemanth V <hemanthv@ti.com> Reviewed-by: Daniel Mack <daniel@caiaq.de> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Cc: Jean Delvare <khali@linux-fr.org> Cc: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hemanth V · Linus Torvalds
1 parent 37ed19d5cc
Showing 3 changed files with 284 additions and 0 deletions Side-by-side Diff
drivers/misc/Kconfig
drivers/misc/Makefile
drivers/misc/bh1780gli.c
@@ -304,6 +304,16 @@
 	  This driver can also be built as a module.  If so, the module
 	  will be called tsl2550.
  
+config SENSORS_BH1780
+	tristate "ROHM BH1780GLI ambient light sensor"
+	depends on I2C && SYSFS
+	help
+	  If you say yes here you get support for the ROHM BH1780GLI
+	  ambient light sensor.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called bh1780gli.
+
 config EP93XX_PWM
 	tristate "EP93xx PWM support"
 	depends on ARCH_EP93XX
@@ -14,6 +14,7 @@
 obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o
 obj-$(CONFIG_TIFM_7XX1)       	+= tifm_7xx1.o
 obj-$(CONFIG_PHANTOM)		+= phantom.o
+obj-$(CONFIG_SENSORS_BH1780)	+= bh1780gli.o
 obj-$(CONFIG_SGI_IOC4)		+= ioc4.o
 obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
 obj-$(CONFIG_KGDB_TESTS)	+= kgdbts.o
+/*
+ * bh1780gli.c
+ * ROHM Ambient Light Sensor Driver
+ *
+ * Copyright (C) 2010 Texas Instruments
+ * Author: Hemanth V <hemanthv@ti.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/i2c.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+
+#define BH1780_REG_CONTROL	0x80
+#define BH1780_REG_PARTID	0x8A
+#define BH1780_REG_MANFID	0x8B
+#define BH1780_REG_DLOW	0x8C
+#define BH1780_REG_DHIGH	0x8D
+
+#define BH1780_REVMASK		(0xf)
+#define BH1780_POWMASK		(0x3)
+#define BH1780_POFF		(0x0)
+#define BH1780_PON		(0x3)
+
+/* power on settling time in ms */
+#define BH1780_PON_DELAY	2
+
+struct bh1780_data {
+	struct i2c_client *client;
+	int power_state;
+	/* lock for sysfs operations */
+	struct mutex lock;
+};
+
+static int bh1780_write(struct bh1780_data *ddata, u8 reg, u8 val, char *msg)
+{
+	int ret = i2c_smbus_write_byte_data(ddata->client, reg, val);
+	if (ret < 0)
+		dev_err(&ddata->client->dev,
+			"i2c_smbus_write_byte_data failed error %d\
+			Register (%s)\n", ret, msg);
+	return ret;
+}
+
+static int bh1780_read(struct bh1780_data *ddata, u8 reg, char *msg)
+{
+	int ret = i2c_smbus_read_byte_data(ddata->client, reg);
+	if (ret < 0)
+		dev_err(&ddata->client->dev,
+			"i2c_smbus_read_byte_data failed error %d\
+			 Register (%s)\n", ret, msg);
+	return ret;
+}
+
+static ssize_t bh1780_show_lux(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct bh1780_data *ddata = platform_get_drvdata(pdev);
+	int lsb, msb;
+
+	lsb = bh1780_read(ddata, BH1780_REG_DLOW, "DLOW");
+	if (lsb < 0)
+		return lsb;
+
+	msb = bh1780_read(ddata, BH1780_REG_DHIGH, "DHIGH");
+	if (msb < 0)
+		return msb;
+
+	return sprintf(buf, "%d\n", (msb << 8) | lsb);
+}
+
+static ssize_t bh1780_show_power_state(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct bh1780_data *ddata = platform_get_drvdata(pdev);
+	int state;
+
+	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
+	if (state < 0)
+		return state;
+
+	return sprintf(buf, "%d\n", state & BH1780_POWMASK);
+}
+
+static ssize_t bh1780_store_power_state(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct bh1780_data *ddata = platform_get_drvdata(pdev);
+	unsigned long val;
+	int error;
+
+	error = strict_strtoul(buf, 0, &val);
+	if (error)
+		return error;
+
+	if (val < BH1780_POFF || val > BH1780_PON)
+		return -EINVAL;
+
+	mutex_lock(&ddata->lock);
+
+	error = bh1780_write(ddata, BH1780_REG_CONTROL, val, "CONTROL");
+	if (error < 0) {
+		mutex_unlock(&ddata->lock);
+		return error;
+	}
+
+	msleep(BH1780_PON_DELAY);
+	ddata->power_state = val;
+	mutex_unlock(&ddata->lock);
+
+	return count;
+}
+
+static DEVICE_ATTR(lux, S_IRUGO, bh1780_show_lux, NULL);
+
+static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
+		bh1780_show_power_state, bh1780_store_power_state);
+
+static struct attribute *bh1780_attributes[] = {
+	&dev_attr_power_state.attr,
+	&dev_attr_lux.attr,
+	NULL
+};
+
+static const struct attribute_group bh1780_attr_group = {
+	.attrs = bh1780_attributes,
+};
+
+static int __devinit bh1780_probe(struct i2c_client *client,
+						const struct i2c_device_id *id)
+{
+	int ret;
+	struct bh1780_data *ddata = NULL;
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) {
+		ret = -EIO;
+		goto err_op_failed;
+	}
+
+	ddata = kzalloc(sizeof(struct bh1780_data), GFP_KERNEL);
+	if (ddata == NULL) {
+		ret = -ENOMEM;
+		goto err_op_failed;
+	}
+
+	ddata->client = client;
+	i2c_set_clientdata(client, ddata);
+
+	ret = bh1780_read(ddata, BH1780_REG_PARTID, "PART ID");
+	if (ret < 0)
+		goto err_op_failed;
+
+	dev_info(&client->dev, "Ambient Light Sensor, Rev : %d\n",
+			(ret & BH1780_REVMASK));
+
+	mutex_init(&ddata->lock);
+
+	ret = sysfs_create_group(&client->dev.kobj, &bh1780_attr_group);
+	if (ret)
+		goto err_op_failed;
+
+	return 0;
+
+err_op_failed:
+	kfree(ddata);
+	return ret;
+}
+
+static int __devexit bh1780_remove(struct i2c_client *client)
+{
+	struct bh1780_data *ddata;
+
+	ddata = i2c_get_clientdata(client);
+	sysfs_remove_group(&client->dev.kobj, &bh1780_attr_group);
+	i2c_set_clientdata(client, NULL);
+	kfree(ddata);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int bh1780_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+	struct bh1780_data *ddata;
+	int state, ret;
+
+	ddata = i2c_get_clientdata(client);
+	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
+	if (state < 0)
+		return state;
+
+	ddata->power_state = state & BH1780_POWMASK;
+
+	ret = bh1780_write(ddata, BH1780_REG_CONTROL, BH1780_POFF,
+				"CONTROL");
+
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int bh1780_resume(struct i2c_client *client)
+{
+	struct bh1780_data *ddata;
+	int state, ret;
+
+	ddata = i2c_get_clientdata(client);
+	state = ddata->power_state;
+
+	ret = bh1780_write(ddata, BH1780_REG_CONTROL, state,
+				"CONTROL");
+
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+#else
+#define bh1780_suspend NULL
+#define bh1780_resume NULL
+#endif /* CONFIG_PM */
+
+static const struct i2c_device_id bh1780_id[] = {
+	{ "bh1780", 0 },
+	{ },
+};
+
+static struct i2c_driver bh1780_driver = {
+	.probe		= bh1780_probe,
+	.remove		= bh1780_remove,
+	.id_table	= bh1780_id,
+	.suspend	= bh1780_suspend,
+	.resume		= bh1780_resume,
+	.driver = {
+		.name = "bh1780"
+	},
+};
+
+static int __init bh1780_init(void)
+{
+	return i2c_add_driver(&bh1780_driver);
+}
+
+static void __exit bh1780_exit(void)
+{
+	i2c_del_driver(&bh1780_driver);
+}
+
+module_init(bh1780_init)
+module_exit(bh1780_exit)
+
+MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");
...	...	@@ -304,6 +304,16 @@
304	304	This driver can also be built as a module. If so, the module
305	305	will be called tsl2550.
306	306
	307	+config SENSORS_BH1780
	308	+ tristate "ROHM BH1780GLI ambient light sensor"
	309	+ depends on I2C && SYSFS
	310	+ help
	311	+ If you say yes here you get support for the ROHM BH1780GLI
	312	+ ambient light sensor.
	313	+
	314	+ This driver can also be built as a module. If so, the module
	315	+ will be called bh1780gli.
	316	+
307	317	config EP93XX_PWM
308	318	tristate "EP93xx PWM support"
309	319	depends on ARCH_EP93XX
...	...	@@ -14,6 +14,7 @@
14	14	obj-$(CONFIG_TIFM_CORE) += tifm_core.o
15	15	obj-$(CONFIG_TIFM_7XX1) += tifm_7xx1.o
16	16	obj-$(CONFIG_PHANTOM) += phantom.o
	17	+obj-$(CONFIG_SENSORS_BH1780) += bh1780gli.o
17	18	obj-$(CONFIG_SGI_IOC4) += ioc4.o
18	19	obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
19	20	obj-$(CONFIG_KGDB_TESTS) += kgdbts.o
	1	+/*
	2	+ * bh1780gli.c
	3	+ * ROHM Ambient Light Sensor Driver
	4	+ *
	5	+ * Copyright (C) 2010 Texas Instruments
	6	+ * Author: Hemanth V <hemanthv@ti.com>
	7	+ *
	8	+ * This program is free software; you can redistribute it and/or modify it
	9	+ * under the terms of the GNU General Public License version 2 as published by
	10	+ * the Free Software Foundation.
	11	+ *
	12	+ * This program is distributed in the hope that it will be useful, but WITHOUT
	13	+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	14	+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	15	+ * more details.
	16	+ *
	17	+ * You should have received a copy of the GNU General Public License along with
	18	+ * this program. If not, see <http://www.gnu.org/licenses/>.
	19	+ */
	20	+#include <linux/i2c.h>
	21	+#include <linux/slab.h>
	22	+#include <linux/mutex.h>
	23	+#include <linux/platform_device.h>
	24	+#include <linux/delay.h>
	25	+
	26	+#define BH1780_REG_CONTROL 0x80
	27	+#define BH1780_REG_PARTID 0x8A
	28	+#define BH1780_REG_MANFID 0x8B
	29	+#define BH1780_REG_DLOW 0x8C
	30	+#define BH1780_REG_DHIGH 0x8D
	31	+
	32	+#define BH1780_REVMASK (0xf)
	33	+#define BH1780_POWMASK (0x3)
	34	+#define BH1780_POFF (0x0)
	35	+#define BH1780_PON (0x3)
	36	+
	37	+/* power on settling time in ms */
	38	+#define BH1780_PON_DELAY 2
	39	+
	40	+struct bh1780_data {
	41	+ struct i2c_client *client;
	42	+ int power_state;
	43	+ /* lock for sysfs operations */
	44	+ struct mutex lock;
	45	+};
	46	+
	47	+static int bh1780_write(struct bh1780_data ddata, u8 reg, u8 val, char msg)
	48	+{
	49	+ int ret = i2c_smbus_write_byte_data(ddata->client, reg, val);
	50	+ if (ret < 0)
	51	+ dev_err(&ddata->client->dev,
	52	+ "i2c_smbus_write_byte_data failed error %d\
	53	+ Register (%s)\n", ret, msg);
	54	+ return ret;
	55	+}
	56	+
	57	+static int bh1780_read(struct bh1780_data ddata, u8 reg, char msg)
	58	+{
	59	+ int ret = i2c_smbus_read_byte_data(ddata->client, reg);
	60	+ if (ret < 0)
	61	+ dev_err(&ddata->client->dev,
	62	+ "i2c_smbus_read_byte_data failed error %d\
	63	+ Register (%s)\n", ret, msg);
	64	+ return ret;
	65	+}
	66	+
	67	+static ssize_t bh1780_show_lux(struct device *dev,
	68	+ struct device_attribute attr, char buf)
	69	+{
	70	+ struct platform_device *pdev = to_platform_device(dev);
	71	+ struct bh1780_data *ddata = platform_get_drvdata(pdev);
	72	+ int lsb, msb;
	73	+
	74	+ lsb = bh1780_read(ddata, BH1780_REG_DLOW, "DLOW");
	75	+ if (lsb < 0)
	76	+ return lsb;
	77	+
	78	+ msb = bh1780_read(ddata, BH1780_REG_DHIGH, "DHIGH");
	79	+ if (msb < 0)
	80	+ return msb;
	81	+
	82	+ return sprintf(buf, "%d\n", (msb << 8) \| lsb);
	83	+}
	84	+
	85	+static ssize_t bh1780_show_power_state(struct device *dev,
	86	+ struct device_attribute *attr,
	87	+ char *buf)
	88	+{
	89	+ struct platform_device *pdev = to_platform_device(dev);
	90	+ struct bh1780_data *ddata = platform_get_drvdata(pdev);
	91	+ int state;
	92	+
	93	+ state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	94	+ if (state < 0)
	95	+ return state;
	96	+
	97	+ return sprintf(buf, "%d\n", state & BH1780_POWMASK);
	98	+}
	99	+
	100	+static ssize_t bh1780_store_power_state(struct device *dev,
	101	+ struct device_attribute *attr,
	102	+ const char *buf, size_t count)
	103	+{
	104	+ struct platform_device *pdev = to_platform_device(dev);
	105	+ struct bh1780_data *ddata = platform_get_drvdata(pdev);
	106	+ unsigned long val;
	107	+ int error;
	108	+
	109	+ error = strict_strtoul(buf, 0, &val);
	110	+ if (error)
	111	+ return error;
	112	+
	113	+ if (val < BH1780_POFF \|\| val > BH1780_PON)
	114	+ return -EINVAL;
	115	+
	116	+ mutex_lock(&ddata->lock);
	117	+
	118	+ error = bh1780_write(ddata, BH1780_REG_CONTROL, val, "CONTROL");
	119	+ if (error < 0) {
	120	+ mutex_unlock(&ddata->lock);
	121	+ return error;
	122	+ }
	123	+
	124	+ msleep(BH1780_PON_DELAY);
	125	+ ddata->power_state = val;
	126	+ mutex_unlock(&ddata->lock);
	127	+
	128	+ return count;
	129	+}
	130	+
	131	+static DEVICE_ATTR(lux, S_IRUGO, bh1780_show_lux, NULL);
	132	+
	133	+static DEVICE_ATTR(power_state, S_IWUSR \| S_IRUGO,
	134	+ bh1780_show_power_state, bh1780_store_power_state);
	135	+
	136	+static struct attribute *bh1780_attributes[] = {
	137	+ &dev_attr_power_state.attr,
	138	+ &dev_attr_lux.attr,
	139	+ NULL
	140	+};
	141	+
	142	+static const struct attribute_group bh1780_attr_group = {
	143	+ .attrs = bh1780_attributes,
	144	+};
	145	+
	146	+static int __devinit bh1780_probe(struct i2c_client *client,
	147	+ const struct i2c_device_id *id)
	148	+{
	149	+ int ret;
	150	+ struct bh1780_data *ddata = NULL;
	151	+ struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	152	+
	153	+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) {
	154	+ ret = -EIO;
	155	+ goto err_op_failed;
	156	+ }
	157	+
	158	+ ddata = kzalloc(sizeof(struct bh1780_data), GFP_KERNEL);
	159	+ if (ddata == NULL) {
	160	+ ret = -ENOMEM;
	161	+ goto err_op_failed;
	162	+ }
	163	+
	164	+ ddata->client = client;
	165	+ i2c_set_clientdata(client, ddata);
	166	+
	167	+ ret = bh1780_read(ddata, BH1780_REG_PARTID, "PART ID");
	168	+ if (ret < 0)
	169	+ goto err_op_failed;
	170	+
	171	+ dev_info(&client->dev, "Ambient Light Sensor, Rev : %d\n",
	172	+ (ret & BH1780_REVMASK));
	173	+
	174	+ mutex_init(&ddata->lock);
	175	+
	176	+ ret = sysfs_create_group(&client->dev.kobj, &bh1780_attr_group);
	177	+ if (ret)
	178	+ goto err_op_failed;
	179	+
	180	+ return 0;
	181	+
	182	+err_op_failed:
	183	+ kfree(ddata);
	184	+ return ret;
	185	+}
	186	+
	187	+static int __devexit bh1780_remove(struct i2c_client *client)
	188	+{
	189	+ struct bh1780_data *ddata;
	190	+
	191	+ ddata = i2c_get_clientdata(client);
	192	+ sysfs_remove_group(&client->dev.kobj, &bh1780_attr_group);
	193	+ i2c_set_clientdata(client, NULL);
	194	+ kfree(ddata);
	195	+
	196	+ return 0;
	197	+}
	198	+
	199	+#ifdef CONFIG_PM
	200	+static int bh1780_suspend(struct i2c_client *client, pm_message_t mesg)
	201	+{
	202	+ struct bh1780_data *ddata;
	203	+ int state, ret;
	204	+
	205	+ ddata = i2c_get_clientdata(client);
	206	+ state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	207	+ if (state < 0)
	208	+ return state;
	209	+
	210	+ ddata->power_state = state & BH1780_POWMASK;
	211	+
	212	+ ret = bh1780_write(ddata, BH1780_REG_CONTROL, BH1780_POFF,
	213	+ "CONTROL");
	214	+
	215	+ if (ret < 0)
	216	+ return ret;
	217	+
	218	+ return 0;
	219	+}
	220	+
	221	+static int bh1780_resume(struct i2c_client *client)
	222	+{
	223	+ struct bh1780_data *ddata;
	224	+ int state, ret;
	225	+
	226	+ ddata = i2c_get_clientdata(client);
	227	+ state = ddata->power_state;
	228	+
	229	+ ret = bh1780_write(ddata, BH1780_REG_CONTROL, state,
	230	+ "CONTROL");
	231	+
	232	+ if (ret < 0)
	233	+ return ret;
	234	+
	235	+ return 0;
	236	+}
	237	+#else
	238	+#define bh1780_suspend NULL
	239	+#define bh1780_resume NULL
	240	+#endif /* CONFIG_PM */
	241	+
	242	+static const struct i2c_device_id bh1780_id[] = {
	243	+ { "bh1780", 0 },
	244	+ { },
	245	+};
	246	+
	247	+static struct i2c_driver bh1780_driver = {
	248	+ .probe = bh1780_probe,
	249	+ .remove = bh1780_remove,
	250	+ .id_table = bh1780_id,
	251	+ .suspend = bh1780_suspend,
	252	+ .resume = bh1780_resume,
	253	+ .driver = {
	254	+ .name = "bh1780"
	255	+ },
	256	+};
	257	+
	258	+static int __init bh1780_init(void)
	259	+{
	260	+ return i2c_add_driver(&bh1780_driver);
	261	+}
	262	+
	263	+static void __exit bh1780_exit(void)
	264	+{
	265	+ i2c_del_driver(&bh1780_driver);
	266	+}
	267	+
	268	+module_init(bh1780_init)
	269	+module_exit(bh1780_exit)
	270	+
	271	+MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver");
	272	+MODULE_LICENSE("GPL");
	273	+MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");