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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/misc/tsl2550.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/misc/tsl2550.c')
-rw-r--r--drivers/misc/tsl2550.c450
1 files changed, 450 insertions, 0 deletions
diff --git a/drivers/misc/tsl2550.c b/drivers/misc/tsl2550.c
new file mode 100644
index 000000000..03f19eda6
--- /dev/null
+++ b/drivers/misc/tsl2550.c
@@ -0,0 +1,450 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * tsl2550.c - Linux kernel modules for ambient light sensor
+ *
+ * Copyright (C) 2007 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (C) 2007 Eurotech S.p.A. <info@eurotech.it>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+
+#define TSL2550_DRV_NAME "tsl2550"
+#define DRIVER_VERSION "1.2"
+
+/*
+ * Defines
+ */
+
+#define TSL2550_POWER_DOWN 0x00
+#define TSL2550_POWER_UP 0x03
+#define TSL2550_STANDARD_RANGE 0x18
+#define TSL2550_EXTENDED_RANGE 0x1d
+#define TSL2550_READ_ADC0 0x43
+#define TSL2550_READ_ADC1 0x83
+
+/*
+ * Structs
+ */
+
+struct tsl2550_data {
+ struct i2c_client *client;
+ struct mutex update_lock;
+
+ unsigned int power_state:1;
+ unsigned int operating_mode:1;
+};
+
+/*
+ * Global data
+ */
+
+static const u8 TSL2550_MODE_RANGE[2] = {
+ TSL2550_STANDARD_RANGE, TSL2550_EXTENDED_RANGE,
+};
+
+/*
+ * Management functions
+ */
+
+static int tsl2550_set_operating_mode(struct i2c_client *client, int mode)
+{
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+
+ int ret = i2c_smbus_write_byte(client, TSL2550_MODE_RANGE[mode]);
+
+ data->operating_mode = mode;
+
+ return ret;
+}
+
+static int tsl2550_set_power_state(struct i2c_client *client, int state)
+{
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+ int ret;
+
+ if (state == 0)
+ ret = i2c_smbus_write_byte(client, TSL2550_POWER_DOWN);
+ else {
+ ret = i2c_smbus_write_byte(client, TSL2550_POWER_UP);
+
+ /* On power up we should reset operating mode also... */
+ tsl2550_set_operating_mode(client, data->operating_mode);
+ }
+
+ data->power_state = state;
+
+ return ret;
+}
+
+static int tsl2550_get_adc_value(struct i2c_client *client, u8 cmd)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(client, cmd);
+ if (ret < 0)
+ return ret;
+ if (!(ret & 0x80))
+ return -EAGAIN;
+ return ret & 0x7f; /* remove the "valid" bit */
+}
+
+/*
+ * LUX calculation
+ */
+
+#define TSL2550_MAX_LUX 1846
+
+static const u8 ratio_lut[] = {
+ 100, 100, 100, 100, 100, 100, 100, 100,
+ 100, 100, 100, 100, 100, 100, 99, 99,
+ 99, 99, 99, 99, 99, 99, 99, 99,
+ 99, 99, 99, 98, 98, 98, 98, 98,
+ 98, 98, 97, 97, 97, 97, 97, 96,
+ 96, 96, 96, 95, 95, 95, 94, 94,
+ 93, 93, 93, 92, 92, 91, 91, 90,
+ 89, 89, 88, 87, 87, 86, 85, 84,
+ 83, 82, 81, 80, 79, 78, 77, 75,
+ 74, 73, 71, 69, 68, 66, 64, 62,
+ 60, 58, 56, 54, 52, 49, 47, 44,
+ 42, 41, 40, 40, 39, 39, 38, 38,
+ 37, 37, 37, 36, 36, 36, 35, 35,
+ 35, 35, 34, 34, 34, 34, 33, 33,
+ 33, 33, 32, 32, 32, 32, 32, 31,
+ 31, 31, 31, 31, 30, 30, 30, 30,
+ 30,
+};
+
+static const u16 count_lut[] = {
+ 0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 18, 20, 22, 24, 26, 28, 30,
+ 32, 34, 36, 38, 40, 42, 44, 46,
+ 49, 53, 57, 61, 65, 69, 73, 77,
+ 81, 85, 89, 93, 97, 101, 105, 109,
+ 115, 123, 131, 139, 147, 155, 163, 171,
+ 179, 187, 195, 203, 211, 219, 227, 235,
+ 247, 263, 279, 295, 311, 327, 343, 359,
+ 375, 391, 407, 423, 439, 455, 471, 487,
+ 511, 543, 575, 607, 639, 671, 703, 735,
+ 767, 799, 831, 863, 895, 927, 959, 991,
+ 1039, 1103, 1167, 1231, 1295, 1359, 1423, 1487,
+ 1551, 1615, 1679, 1743, 1807, 1871, 1935, 1999,
+ 2095, 2223, 2351, 2479, 2607, 2735, 2863, 2991,
+ 3119, 3247, 3375, 3503, 3631, 3759, 3887, 4015,
+};
+
+/*
+ * This function is described into Taos TSL2550 Designer's Notebook
+ * pages 2, 3.
+ */
+static int tsl2550_calculate_lux(u8 ch0, u8 ch1)
+{
+ unsigned int lux;
+
+ /* Look up count from channel values */
+ u16 c0 = count_lut[ch0];
+ u16 c1 = count_lut[ch1];
+
+ /* Avoid division by 0 and count 1 cannot be greater than count 0 */
+ if (c1 <= c0)
+ if (c0) {
+ /*
+ * Calculate ratio.
+ * Note: the "128" is a scaling factor
+ */
+ u8 r = c1 * 128 / c0;
+
+ /* Calculate LUX */
+ lux = ((c0 - c1) * ratio_lut[r]) / 256;
+ } else
+ lux = 0;
+ else
+ return 0;
+
+ /* LUX range check */
+ return lux > TSL2550_MAX_LUX ? TSL2550_MAX_LUX : lux;
+}
+
+/*
+ * SysFS support
+ */
+
+static ssize_t tsl2550_show_power_state(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
+
+ return sprintf(buf, "%u\n", data->power_state);
+}
+
+static ssize_t tsl2550_store_power_state(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+ unsigned long val;
+ int ret;
+
+ if (kstrtoul(buf, 10, &val) || val > 1)
+ return -EINVAL;
+
+ mutex_lock(&data->update_lock);
+ ret = tsl2550_set_power_state(client, val);
+ mutex_unlock(&data->update_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
+ tsl2550_show_power_state, tsl2550_store_power_state);
+
+static ssize_t tsl2550_show_operating_mode(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
+
+ return sprintf(buf, "%u\n", data->operating_mode);
+}
+
+static ssize_t tsl2550_store_operating_mode(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+ unsigned long val;
+ int ret;
+
+ if (kstrtoul(buf, 10, &val) || val > 1)
+ return -EINVAL;
+
+ if (data->power_state == 0)
+ return -EBUSY;
+
+ mutex_lock(&data->update_lock);
+ ret = tsl2550_set_operating_mode(client, val);
+ mutex_unlock(&data->update_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static DEVICE_ATTR(operating_mode, S_IWUSR | S_IRUGO,
+ tsl2550_show_operating_mode, tsl2550_store_operating_mode);
+
+static ssize_t __tsl2550_show_lux(struct i2c_client *client, char *buf)
+{
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+ u8 ch0, ch1;
+ int ret;
+
+ ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC0);
+ if (ret < 0)
+ return ret;
+ ch0 = ret;
+
+ ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC1);
+ if (ret < 0)
+ return ret;
+ ch1 = ret;
+
+ /* Do the job */
+ ret = tsl2550_calculate_lux(ch0, ch1);
+ if (ret < 0)
+ return ret;
+ if (data->operating_mode == 1)
+ ret *= 5;
+
+ return sprintf(buf, "%d\n", ret);
+}
+
+static ssize_t tsl2550_show_lux1_input(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+ int ret;
+
+ /* No LUX data if not operational */
+ if (!data->power_state)
+ return -EBUSY;
+
+ mutex_lock(&data->update_lock);
+ ret = __tsl2550_show_lux(client, buf);
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+static DEVICE_ATTR(lux1_input, S_IRUGO,
+ tsl2550_show_lux1_input, NULL);
+
+static struct attribute *tsl2550_attributes[] = {
+ &dev_attr_power_state.attr,
+ &dev_attr_operating_mode.attr,
+ &dev_attr_lux1_input.attr,
+ NULL
+};
+
+static const struct attribute_group tsl2550_attr_group = {
+ .attrs = tsl2550_attributes,
+};
+
+/*
+ * Initialization function
+ */
+
+static int tsl2550_init_client(struct i2c_client *client)
+{
+ struct tsl2550_data *data = i2c_get_clientdata(client);
+ int err;
+
+ /*
+ * Probe the chip. To do so we try to power up the device and then to
+ * read back the 0x03 code
+ */
+ err = i2c_smbus_read_byte_data(client, TSL2550_POWER_UP);
+ if (err < 0)
+ return err;
+ if (err != TSL2550_POWER_UP)
+ return -ENODEV;
+ data->power_state = 1;
+
+ /* Set the default operating mode */
+ err = i2c_smbus_write_byte(client,
+ TSL2550_MODE_RANGE[data->operating_mode]);
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
+/*
+ * I2C init/probing/exit functions
+ */
+
+static struct i2c_driver tsl2550_driver;
+static int tsl2550_probe(struct i2c_client *client)
+{
+ struct i2c_adapter *adapter = client->adapter;
+ struct tsl2550_data *data;
+ int *opmode, err = 0;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE
+ | I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
+ err = -EIO;
+ goto exit;
+ }
+
+ data = kzalloc_obj(struct tsl2550_data);
+ if (!data) {
+ err = -ENOMEM;
+ goto exit;
+ }
+ data->client = client;
+ i2c_set_clientdata(client, data);
+
+ /* Check platform data */
+ opmode = client->dev.platform_data;
+ if (opmode) {
+ if (*opmode < 0 || *opmode > 1) {
+ dev_err(&client->dev, "invalid operating_mode (%d)\n",
+ *opmode);
+ err = -EINVAL;
+ goto exit_kfree;
+ }
+ data->operating_mode = *opmode;
+ } else
+ data->operating_mode = 0; /* default mode is standard */
+ dev_info(&client->dev, "%s operating mode\n",
+ data->operating_mode ? "extended" : "standard");
+
+ mutex_init(&data->update_lock);
+
+ /* Initialize the TSL2550 chip */
+ err = tsl2550_init_client(client);
+ if (err)
+ goto exit_kfree;
+
+ /* Register sysfs hooks */
+ err = sysfs_create_group(&client->dev.kobj, &tsl2550_attr_group);
+ if (err)
+ goto exit_kfree;
+
+ dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
+
+ return 0;
+
+exit_kfree:
+ kfree(data);
+exit:
+ return err;
+}
+
+static void tsl2550_remove(struct i2c_client *client)
+{
+ sysfs_remove_group(&client->dev.kobj, &tsl2550_attr_group);
+
+ /* Power down the device */
+ tsl2550_set_power_state(client, 0);
+
+ kfree(i2c_get_clientdata(client));
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int tsl2550_suspend(struct device *dev)
+{
+ return tsl2550_set_power_state(to_i2c_client(dev), 0);
+}
+
+static int tsl2550_resume(struct device *dev)
+{
+ return tsl2550_set_power_state(to_i2c_client(dev), 1);
+}
+
+static SIMPLE_DEV_PM_OPS(tsl2550_pm_ops, tsl2550_suspend, tsl2550_resume);
+#define TSL2550_PM_OPS (&tsl2550_pm_ops)
+
+#else
+
+#define TSL2550_PM_OPS NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct i2c_device_id tsl2550_id[] = {
+ { "tsl2550" },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tsl2550_id);
+
+static const struct of_device_id tsl2550_of_match[] = {
+ { .compatible = "taos,tsl2550" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, tsl2550_of_match);
+
+static struct i2c_driver tsl2550_driver = {
+ .driver = {
+ .name = TSL2550_DRV_NAME,
+ .of_match_table = tsl2550_of_match,
+ .pm = TSL2550_PM_OPS,
+ },
+ .probe = tsl2550_probe,
+ .remove = tsl2550_remove,
+ .id_table = tsl2550_id,
+};
+
+module_i2c_driver(tsl2550_driver);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("TSL2550 ambient light sensor driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRIVER_VERSION);