--- /dev/null
+/*
+ * Copyright (c) 2015 - 2016 Red Hat, Inc
+ * Copyright (c) 2011, 2012 Synaptics Incorporated
+ * Copyright (c) 2011 Unixphere
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kconfig.h>
+#include <linux/lockdep.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/rmi.h>
+#include <linux/slab.h>
+#include "rmi_driver.h"
+
+#define SMB_PROTOCOL_VERSION_ADDRESS 0xfd
+#define SMB_MAX_COUNT 32
+#define RMI_SMB2_MAP_SIZE 8 /* 8 entry of 4 bytes each */
+#define RMI_SMB2_MAP_FLAGS_WE 0x01
+
+struct mapping_table_entry {
+ __le16 rmiaddr;
+ u8 readcount;
+ u8 flags;
+};
+
+struct rmi_smb_xport {
+ struct rmi_transport_dev xport;
+ struct i2c_client *client;
+
+ struct mutex page_mutex;
+ int page;
+ u8 table_index;
+ struct mutex mappingtable_mutex;
+ struct mapping_table_entry mapping_table[RMI_SMB2_MAP_SIZE];
+};
+
+static int rmi_smb_get_version(struct rmi_smb_xport *rmi_smb)
+{
+ struct i2c_client *client = rmi_smb->client;
+ int retval;
+
+ /* Check if for SMBus new version device by reading version byte. */
+ retval = i2c_smbus_read_byte_data(client, SMB_PROTOCOL_VERSION_ADDRESS);
+ if (retval < 0) {
+ dev_err(&client->dev, "failed to get SMBus version number!\n");
+ return retval;
+ }
+ return retval + 1;
+}
+
+/* SMB block write - wrapper over ic2_smb_write_block */
+static int smb_block_write(struct rmi_transport_dev *xport,
+ u8 commandcode, const void *buf, size_t len)
+{
+ struct rmi_smb_xport *rmi_smb =
+ container_of(xport, struct rmi_smb_xport, xport);
+ struct i2c_client *client = rmi_smb->client;
+ int retval;
+
+ retval = i2c_smbus_write_block_data(client, commandcode, len, buf);
+
+ rmi_dbg(RMI_DEBUG_XPORT, &client->dev,
+ "wrote %zd bytes at %#04x: %d (%*ph)\n",
+ len, commandcode, retval, (int)len, buf);
+
+ return retval;
+}
+
+/*
+ * The function to get command code for smbus operations and keeps
+ * records to the driver mapping table
+ */
+static int rmi_smb_get_command_code(struct rmi_transport_dev *xport,
+ u16 rmiaddr, int bytecount, bool isread, u8 *commandcode)
+{
+ struct rmi_smb_xport *rmi_smb =
+ container_of(xport, struct rmi_smb_xport, xport);
+ int i;
+ int retval;
+ struct mapping_table_entry mapping_data[1];
+
+ mutex_lock(&rmi_smb->mappingtable_mutex);
+ for (i = 0; i < RMI_SMB2_MAP_SIZE; i++) {
+ if (rmi_smb->mapping_table[i].rmiaddr == rmiaddr) {
+ if (isread) {
+ if (rmi_smb->mapping_table[i].readcount
+ == bytecount) {
+ *commandcode = i;
+ retval = 0;
+ goto exit;
+ }
+ } else {
+ if (rmi_smb->mapping_table[i].flags &
+ RMI_SMB2_MAP_FLAGS_WE) {
+ *commandcode = i;
+ retval = 0;
+ goto exit;
+ }
+ }
+ }
+ }
+ i = rmi_smb->table_index;
+ rmi_smb->table_index = (i + 1) % RMI_SMB2_MAP_SIZE;
+
+ /* constructs mapping table data entry. 4 bytes each entry */
+ memset(mapping_data, 0, sizeof(mapping_data));
+
+ mapping_data[0].rmiaddr = cpu_to_le16(rmiaddr);
+ mapping_data[0].readcount = bytecount;
+ mapping_data[0].flags = !isread ? RMI_SMB2_MAP_FLAGS_WE : 0;
+
+ retval = smb_block_write(xport, i + 0x80, mapping_data,
+ sizeof(mapping_data));
+
+ if (retval < 0) {
+ /*
+ * if not written to device mapping table
+ * clear the driver mapping table records
+ */
+ rmi_smb->mapping_table[i].rmiaddr = 0x0000;
+ rmi_smb->mapping_table[i].readcount = 0;
+ rmi_smb->mapping_table[i].flags = 0;
+ goto exit;
+ }
+ /* save to the driver level mapping table */
+ rmi_smb->mapping_table[i].rmiaddr = rmiaddr;
+ rmi_smb->mapping_table[i].readcount = bytecount;
+ rmi_smb->mapping_table[i].flags = !isread ? RMI_SMB2_MAP_FLAGS_WE : 0;
+ *commandcode = i;
+
+exit:
+ mutex_unlock(&rmi_smb->mappingtable_mutex);
+
+ return retval;
+}
+
+static int rmi_smb_write_block(struct rmi_transport_dev *xport, u16 rmiaddr,
+ const void *databuff, size_t len)
+{
+ int retval = 0;
+ u8 commandcode;
+ struct rmi_smb_xport *rmi_smb =
+ container_of(xport, struct rmi_smb_xport, xport);
+ int cur_len = (int)len;
+
+ mutex_lock(&rmi_smb->page_mutex);
+
+ while (cur_len > 0) {
+ /*
+ * break into 32 bytes chunks to write get command code
+ */
+ int block_len = min_t(int, len, SMB_MAX_COUNT);
+
+ retval = rmi_smb_get_command_code(xport, rmiaddr, block_len,
+ false, &commandcode);
+ if (retval < 0)
+ goto exit;
+
+ retval = smb_block_write(xport, commandcode,
+ databuff, block_len);
+ if (retval < 0)
+ goto exit;
+
+ /* prepare to write next block of bytes */
+ cur_len -= SMB_MAX_COUNT;
+ databuff += SMB_MAX_COUNT;
+ rmiaddr += SMB_MAX_COUNT;
+ }
+exit:
+ mutex_unlock(&rmi_smb->page_mutex);
+ return retval;
+}
+
+/* SMB block read - wrapper over ic2_smb_read_block */
+static int smb_block_read(struct rmi_transport_dev *xport,
+ u8 commandcode, void *buf, size_t len)
+{
+ struct rmi_smb_xport *rmi_smb =
+ container_of(xport, struct rmi_smb_xport, xport);
+ struct i2c_client *client = rmi_smb->client;
+ int retval;
+
+ retval = i2c_smbus_read_block_data(client, commandcode, buf);
+ if (retval < 0)
+ return retval;
+
+ return retval;
+}
+
+static int rmi_smb_read_block(struct rmi_transport_dev *xport, u16 rmiaddr,
+ void *databuff, size_t len)
+{
+ struct rmi_smb_xport *rmi_smb =
+ container_of(xport, struct rmi_smb_xport, xport);
+ int retval;
+ u8 commandcode;
+ int cur_len = (int)len;
+
+ mutex_lock(&rmi_smb->page_mutex);
+ memset(databuff, 0, len);
+
+ while (cur_len > 0) {
+ /* break into 32 bytes chunks to write get command code */
+ int block_len = min_t(int, cur_len, SMB_MAX_COUNT);
+
+ retval = rmi_smb_get_command_code(xport, rmiaddr, block_len,
+ true, &commandcode);
+ if (retval < 0)
+ goto exit;
+
+ retval = smb_block_read(xport, commandcode,
+ databuff, block_len);
+ if (retval < 0)
+ goto exit;
+
+ /* prepare to read next block of bytes */
+ cur_len -= SMB_MAX_COUNT;
+ databuff += SMB_MAX_COUNT;
+ rmiaddr += SMB_MAX_COUNT;
+ }
+
+ retval = 0;
+
+exit:
+ mutex_unlock(&rmi_smb->page_mutex);
+ return retval;
+}
+
+static void rmi_smb_clear_state(struct rmi_smb_xport *rmi_smb)
+{
+ /* the mapping table has been flushed, discard the current one */
+ mutex_lock(&rmi_smb->mappingtable_mutex);
+ memset(rmi_smb->mapping_table, 0, sizeof(rmi_smb->mapping_table));
+ mutex_unlock(&rmi_smb->mappingtable_mutex);
+}
+
+static int rmi_smb_enable_smbus_mode(struct rmi_smb_xport *rmi_smb)
+{
+ int retval;
+
+ /* we need to get the smbus version to activate the touchpad */
+ retval = rmi_smb_get_version(rmi_smb);
+ if (retval < 0)
+ return retval;
+
+ return 0;
+}
+
+static int rmi_smb_reset(struct rmi_transport_dev *xport, u16 reset_addr)
+{
+ struct rmi_smb_xport *rmi_smb =
+ container_of(xport, struct rmi_smb_xport, xport);
+
+ rmi_smb_clear_state(rmi_smb);
+
+ /*
+ * we do not call the actual reset command, it has to be handled in
+ * PS/2 or there will be races between PS/2 and SMBus.
+ * PS/2 should ensure that a psmouse_reset is called before
+ * intializing the device and after it has been removed to be in a known
+ * state.
+ */
+ return rmi_smb_enable_smbus_mode(rmi_smb);
+}
+
+static const struct rmi_transport_ops rmi_smb_ops = {
+ .write_block = rmi_smb_write_block,
+ .read_block = rmi_smb_read_block,
+ .reset = rmi_smb_reset,
+};
+
+static int rmi_smb_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct rmi_device_platform_data *pdata = dev_get_platdata(&client->dev);
+ struct rmi_smb_xport *rmi_smb;
+ int retval;
+ int smbus_version;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_BLOCK_DATA |
+ I2C_FUNC_SMBUS_HOST_NOTIFY)) {
+ dev_err(&client->dev,
+ "adapter does not support required functionality.\n");
+ return -ENODEV;
+ }
+
+ if (client->irq <= 0) {
+ dev_err(&client->dev, "no IRQ provided, giving up.\n");
+ return client->irq ? client->irq : -ENODEV;
+ }
+
+ rmi_smb = devm_kzalloc(&client->dev, sizeof(struct rmi_smb_xport),
+ GFP_KERNEL);
+ if (!rmi_smb)
+ return -ENOMEM;
+
+ if (!pdata) {
+ dev_err(&client->dev, "no platform data, aborting\n");
+ return -ENOMEM;
+ }
+
+ rmi_dbg(RMI_DEBUG_XPORT, &client->dev, "Probing %s.\n",
+ dev_name(&client->dev));
+
+ rmi_smb->client = client;
+ mutex_init(&rmi_smb->page_mutex);
+ mutex_init(&rmi_smb->mappingtable_mutex);
+
+ rmi_smb->xport.dev = &client->dev;
+ rmi_smb->xport.pdata = *pdata;
+ rmi_smb->xport.pdata.irq = client->irq;
+ rmi_smb->xport.proto_name = "smb2";
+ rmi_smb->xport.ops = &rmi_smb_ops;
+
+ retval = rmi_smb_get_version(rmi_smb);
+ if (retval < 0)
+ return retval;
+
+ smbus_version = retval;
+ rmi_dbg(RMI_DEBUG_XPORT, &client->dev, "Smbus version is %d",
+ smbus_version);
+
+ if (smbus_version != 2) {
+ dev_err(&client->dev, "Unrecognized SMB version %d.\n",
+ smbus_version);
+ return -ENODEV;
+ }
+
+ i2c_set_clientdata(client, rmi_smb);
+
+ retval = rmi_register_transport_device(&rmi_smb->xport);
+ if (retval) {
+ dev_err(&client->dev, "Failed to register transport driver at 0x%.2X.\n",
+ client->addr);
+ i2c_set_clientdata(client, NULL);
+ return retval;
+ }
+
+ dev_info(&client->dev, "registered rmi smb driver at %#04x.\n",
+ client->addr);
+ return 0;
+
+}
+
+static int rmi_smb_remove(struct i2c_client *client)
+{
+ struct rmi_smb_xport *rmi_smb = i2c_get_clientdata(client);
+
+ rmi_unregister_transport_device(&rmi_smb->xport);
+
+ return 0;
+}
+
+static int __maybe_unused rmi_smb_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_smb_xport *rmi_smb = i2c_get_clientdata(client);
+ int ret;
+
+ ret = rmi_driver_suspend(rmi_smb->xport.rmi_dev, true);
+ if (ret)
+ dev_warn(dev, "Failed to suspend device: %d\n", ret);
+
+ return ret;
+}
+
+static int __maybe_unused rmi_smb_runtime_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_smb_xport *rmi_smb = i2c_get_clientdata(client);
+ int ret;
+
+ ret = rmi_driver_suspend(rmi_smb->xport.rmi_dev, false);
+ if (ret)
+ dev_warn(dev, "Failed to suspend device: %d\n", ret);
+
+ return ret;
+}
+
+static int __maybe_unused rmi_smb_resume(struct device *dev)
+{
+ struct i2c_client *client = container_of(dev, struct i2c_client, dev);
+ struct rmi_smb_xport *rmi_smb = i2c_get_clientdata(client);
+ struct rmi_device *rmi_dev = rmi_smb->xport.rmi_dev;
+ int ret;
+
+ rmi_smb_reset(&rmi_smb->xport, 0);
+
+ rmi_reset(rmi_dev);
+
+ ret = rmi_driver_resume(rmi_smb->xport.rmi_dev, true);
+ if (ret)
+ dev_warn(dev, "Failed to resume device: %d\n", ret);
+
+ return 0;
+}
+
+static int __maybe_unused rmi_smb_runtime_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rmi_smb_xport *rmi_smb = i2c_get_clientdata(client);
+ int ret;
+
+ ret = rmi_driver_resume(rmi_smb->xport.rmi_dev, false);
+ if (ret)
+ dev_warn(dev, "Failed to resume device: %d\n", ret);
+
+ return 0;
+}
+
+static const struct dev_pm_ops rmi_smb_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(rmi_smb_suspend, rmi_smb_resume)
+ SET_RUNTIME_PM_OPS(rmi_smb_runtime_suspend, rmi_smb_runtime_resume,
+ NULL)
+};
+
+static const struct i2c_device_id rmi_id[] = {
+ { "rmi4_smbus", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, rmi_id);
+
+static struct i2c_driver rmi_smb_driver = {
+ .driver = {
+ .name = "rmi4_smbus",
+ .pm = &rmi_smb_pm,
+ },
+ .id_table = rmi_id,
+ .probe = rmi_smb_probe,
+ .remove = rmi_smb_remove,
+};
+
+module_i2c_driver(rmi_smb_driver);
+
+MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com>");
+MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@redhat.com>");
+MODULE_DESCRIPTION("RMI4 SMBus driver");
+MODULE_LICENSE("GPL");
projects / mirror_ubuntu-disco-kernel.git / commitdiff