summaryrefslogtreecommitdiffstats
path: root/drivers/input/rmi4/rmi_i2c.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/input/rmi4/rmi_i2c.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/rmi4/rmi_i2c.c')
-rw-r--r--drivers/input/rmi4/rmi_i2c.c394
1 files changed, 394 insertions, 0 deletions
diff --git a/drivers/input/rmi4/rmi_i2c.c b/drivers/input/rmi4/rmi_i2c.c
new file mode 100644
index 000000000..50305fcfb
--- /dev/null
+++ b/drivers/input/rmi4/rmi_i2c.c
@@ -0,0 +1,394 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2011-2016 Synaptics Incorporated
+ * Copyright (c) 2011 Unixphere
+ */
+
+#include <linux/i2c.h>
+#include <linux/rmi.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+#include <linux/regulator/consumer.h>
+#include "rmi_driver.h"
+
+#define BUFFER_SIZE_INCREMENT 32
+
+/**
+ * struct rmi_i2c_xport - stores information for i2c communication
+ *
+ * @xport: The transport interface structure
+ * @client: The I2C client device structure
+ *
+ * @page_mutex: Locks current page to avoid changing pages in unexpected ways.
+ * @page: Keeps track of the current virtual page
+ *
+ * @tx_buf: Buffer used for transmitting data to the sensor over i2c.
+ * @tx_buf_size: Size of the buffer
+ *
+ * @supplies: Array of voltage regulators
+ * @startup_delay: Milliseconds to pause after powering up the regulators
+ */
+struct rmi_i2c_xport {
+ struct rmi_transport_dev xport;
+ struct i2c_client *client;
+
+ struct mutex page_mutex;
+ int page;
+
+ u8 *tx_buf;
+ size_t tx_buf_size;
+
+ struct regulator_bulk_data supplies[2];
+ u32 startup_delay;
+};
+
+#define RMI_PAGE_SELECT_REGISTER 0xff
+#define RMI_I2C_PAGE(addr) (((addr) >> 8) & 0xff)
+
+/*
+ * rmi_set_page - Set RMI page
+ * @xport: The pointer to the rmi_transport_dev struct
+ * @page: The new page address.
+ *
+ * RMI devices have 16-bit addressing, but some of the transport
+ * implementations (like SMBus) only have 8-bit addressing. So RMI implements
+ * a page address at 0xff of every page so we can reliable page addresses
+ * every 256 registers.
+ *
+ * The page_mutex lock must be held when this function is entered.
+ *
+ * Returns zero on success, non-zero on failure.
+ */
+static int rmi_set_page(struct rmi_i2c_xport *rmi_i2c, u8 page)
+{
+ struct i2c_client *client = rmi_i2c->client;
+ u8 txbuf[2] = {RMI_PAGE_SELECT_REGISTER, page};
+ int retval;
+
+ retval = i2c_master_send(client, txbuf, sizeof(txbuf));
+ if (retval != sizeof(txbuf)) {
+ dev_err(&client->dev,
+ "%s: set page failed: %d.", __func__, retval);
+ return (retval < 0) ? retval : -EIO;
+ }
+
+ rmi_i2c->page = page;
+ return 0;
+}
+
+static int rmi_i2c_write_block(struct rmi_transport_dev *xport, u16 addr,
+ const void *buf, size_t len)
+{
+ struct rmi_i2c_xport *rmi_i2c =
+ container_of(xport, struct rmi_i2c_xport, xport);
+ struct i2c_client *client = rmi_i2c->client;
+ size_t tx_size = len + 1;
+ int retval;
+
+ mutex_lock(&rmi_i2c->page_mutex);
+
+ if (!rmi_i2c->tx_buf || rmi_i2c->tx_buf_size < tx_size) {
+ if (rmi_i2c->tx_buf)
+ devm_kfree(&client->dev, rmi_i2c->tx_buf);
+ rmi_i2c->tx_buf_size = tx_size + BUFFER_SIZE_INCREMENT;
+ rmi_i2c->tx_buf = devm_kzalloc(&client->dev,
+ rmi_i2c->tx_buf_size,
+ GFP_KERNEL);
+ if (!rmi_i2c->tx_buf) {
+ rmi_i2c->tx_buf_size = 0;
+ retval = -ENOMEM;
+ goto exit;
+ }
+ }
+
+ rmi_i2c->tx_buf[0] = addr & 0xff;
+ memcpy(rmi_i2c->tx_buf + 1, buf, len);
+
+ if (RMI_I2C_PAGE(addr) != rmi_i2c->page) {
+ retval = rmi_set_page(rmi_i2c, RMI_I2C_PAGE(addr));
+ if (retval)
+ goto exit;
+ }
+
+ retval = i2c_master_send(client, rmi_i2c->tx_buf, tx_size);
+ if (retval == tx_size)
+ retval = 0;
+ else if (retval >= 0)
+ retval = -EIO;
+
+exit:
+ rmi_dbg(RMI_DEBUG_XPORT, &client->dev,
+ "write %zd bytes at %#06x: %d (%*ph)\n",
+ len, addr, retval, (int)len, buf);
+
+ mutex_unlock(&rmi_i2c->page_mutex);
+ return retval;
+}
+
+static int rmi_i2c_read_block(struct rmi_transport_dev *xport, u16 addr,
+ void *buf, size_t len)
+{
+ struct rmi_i2c_xport *rmi_i2c =
+ container_of(xport, struct rmi_i2c_xport, xport);
+ struct i2c_client *client = rmi_i2c->client;
+ u8 addr_offset = addr & 0xff;
+ int retval;
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .len = sizeof(addr_offset),
+ .buf = &addr_offset,
+ },
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = len,
+ .buf = buf,
+ },
+ };
+
+ mutex_lock(&rmi_i2c->page_mutex);
+
+ if (RMI_I2C_PAGE(addr) != rmi_i2c->page) {
+ retval = rmi_set_page(rmi_i2c, RMI_I2C_PAGE(addr));
+ if (retval)
+ goto exit;
+ }
+
+ retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (retval == ARRAY_SIZE(msgs))
+ retval = 0; /* success */
+ else if (retval >= 0)
+ retval = -EIO;
+
+exit:
+ rmi_dbg(RMI_DEBUG_XPORT, &client->dev,
+ "read %zd bytes at %#06x: %d (%*ph)\n",
+ len, addr, retval, (int)len, buf);
+
+ mutex_unlock(&rmi_i2c->page_mutex);
+ return retval;
+}
+
+static const struct rmi_transport_ops rmi_i2c_ops = {
+ .write_block = rmi_i2c_write_block,
+ .read_block = rmi_i2c_read_block,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id rmi_i2c_of_match[] = {
+ { .compatible = "syna,rmi4-i2c" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, rmi_i2c_of_match);
+#endif
+
+static void rmi_i2c_regulator_bulk_disable(void *data)
+{
+ struct rmi_i2c_xport *rmi_i2c = data;
+
+ regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+}
+
+static void rmi_i2c_unregister_transport(void *data)
+{
+ struct rmi_i2c_xport *rmi_i2c = data;
+
+ rmi_unregister_transport_device(&rmi_i2c->xport);
+}
+
+static int rmi_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct rmi_device_platform_data *pdata;
+ struct rmi_device_platform_data *client_pdata =
+ dev_get_platdata(&client->dev);
+ struct rmi_i2c_xport *rmi_i2c;
+ int error;
+
+ rmi_i2c = devm_kzalloc(&client->dev, sizeof(struct rmi_i2c_xport),
+ GFP_KERNEL);
+ if (!rmi_i2c)
+ return -ENOMEM;
+
+ pdata = &rmi_i2c->xport.pdata;
+
+ if (!client->dev.of_node && client_pdata)
+ *pdata = *client_pdata;
+
+ pdata->irq = client->irq;
+
+ rmi_dbg(RMI_DEBUG_XPORT, &client->dev, "Probing %s.\n",
+ dev_name(&client->dev));
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(&client->dev,
+ "adapter does not support required functionality\n");
+ return -ENODEV;
+ }
+
+ rmi_i2c->supplies[0].supply = "vdd";
+ rmi_i2c->supplies[1].supply = "vio";
+ error = devm_regulator_bulk_get(&client->dev,
+ ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+ if (error < 0)
+ return error;
+
+ error = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+ if (error < 0)
+ return error;
+
+ error = devm_add_action_or_reset(&client->dev,
+ rmi_i2c_regulator_bulk_disable,
+ rmi_i2c);
+ if (error)
+ return error;
+
+ of_property_read_u32(client->dev.of_node, "syna,startup-delay-ms",
+ &rmi_i2c->startup_delay);
+
+ msleep(rmi_i2c->startup_delay);
+
+ rmi_i2c->client = client;
+ mutex_init(&rmi_i2c->page_mutex);
+
+ rmi_i2c->xport.dev = &client->dev;
+ rmi_i2c->xport.proto_name = "i2c";
+ rmi_i2c->xport.ops = &rmi_i2c_ops;
+
+ i2c_set_clientdata(client, rmi_i2c);
+
+ /*
+ * Setting the page to zero will (a) make sure the PSR is in a
+ * known state, and (b) make sure we can talk to the device.
+ */
+ error = rmi_set_page(rmi_i2c, 0);
+ if (error) {
+ dev_err(&client->dev, "Failed to set page select to 0\n");
+ return error;
+ }
+
+ dev_info(&client->dev, "registering I2C-connected sensor\n");
+
+ error = rmi_register_transport_device(&rmi_i2c->xport);
+ if (error) {
+ dev_err(&client->dev, "failed to register sensor: %d\n", error);
+ return error;
+ }
+
+ error = devm_add_action_or_reset(&client->dev,
+ rmi_i2c_unregister_transport,
+ rmi_i2c);
+ if (error)
+ return error;
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int rmi_i2c_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
+ int ret;
+
+ ret = rmi_driver_suspend(rmi_i2c->xport.rmi_dev, true);
+ if (ret)
+ dev_warn(dev, "Failed to resume device: %d\n", ret);
+
+ regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+
+ return ret;
+}
+
+static int rmi_i2c_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+ if (ret)
+ return ret;
+
+ msleep(rmi_i2c->startup_delay);
+
+ ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev, true);
+ if (ret)
+ dev_warn(dev, "Failed to resume device: %d\n", ret);
+
+ return ret;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int rmi_i2c_runtime_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
+ int ret;
+
+ ret = rmi_driver_suspend(rmi_i2c->xport.rmi_dev, false);
+ if (ret)
+ dev_warn(dev, "Failed to resume device: %d\n", ret);
+
+ regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+
+ return 0;
+}
+
+static int rmi_i2c_runtime_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies),
+ rmi_i2c->supplies);
+ if (ret)
+ return ret;
+
+ msleep(rmi_i2c->startup_delay);
+
+ ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev, false);
+ if (ret)
+ dev_warn(dev, "Failed to resume device: %d\n", ret);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops rmi_i2c_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(rmi_i2c_suspend, rmi_i2c_resume)
+ SET_RUNTIME_PM_OPS(rmi_i2c_runtime_suspend, rmi_i2c_runtime_resume,
+ NULL)
+};
+
+static const struct i2c_device_id rmi_id[] = {
+ { "rmi4_i2c", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, rmi_id);
+
+static struct i2c_driver rmi_i2c_driver = {
+ .driver = {
+ .name = "rmi4_i2c",
+ .pm = &rmi_i2c_pm,
+ .of_match_table = of_match_ptr(rmi_i2c_of_match),
+ },
+ .id_table = rmi_id,
+ .probe = rmi_i2c_probe,
+};
+
+module_i2c_driver(rmi_i2c_driver);
+
+MODULE_AUTHOR("Christopher Heiny <cheiny@synaptics.com>");
+MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com>");
+MODULE_DESCRIPTION("RMI I2C driver");
+MODULE_LICENSE("GPL");