tpm/st33zp24: Add support for acpi probing for i2c device.

[deliverable/linux.git] / drivers / char / tpm / st33zp24 / i2c.c

diff --git a/drivers/char/tpm/st33zp24/i2c.c b/drivers/char/tpm/st33zp24/i2c.c
index 309d2767c6a109c27cd73a833f9670a7360cd521..b20cc2ba98ccd2044c511f13837e566a094e69b4 100644 (file)
--- a/drivers/char/tpm/st33zp24/i2c.c
+++ b/drivers/char/tpm/st33zp24/i2c.c
@@ -1,6 +1,6 @@
 /*
  * STMicroelectronics TPM I2C Linux driver for TPM ST33ZP24
- * Copyright (C) 2009 - 2015 STMicroelectronics
+ * Copyright (C) 2009 - 2016 STMicroelectronics
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -19,8 +19,10 @@
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/of_irq.h>
 #include <linux/of_gpio.h>
+#include <linux/acpi.h>
 #include <linux/tpm.h>
 #include <linux/platform_data/st33zp24.h>
 
@@ -108,7 +110,43 @@ static const struct st33zp24_phy_ops i2c_phy_ops = {
        .recv = st33zp24_i2c_recv,
 };
 
-#ifdef CONFIG_OF
+static int st33zp24_i2c_acpi_request_resources(struct st33zp24_i2c_phy *phy)
+{
+       struct i2c_client *client = phy->client;
+       const struct acpi_device_id *id;
+       struct gpio_desc *gpiod_lpcpd;
+       struct device *dev;
+
+       if (!client)
+               return -EINVAL;
+
+       dev = &client->dev;
+
+       /* Match the struct device against a given list of ACPI IDs */
+       id = acpi_match_device(dev->driver->acpi_match_table, dev);
+       if (!id)
+               return -ENODEV;
+
+       /* Get LPCPD GPIO from ACPI */
+       gpiod_lpcpd = devm_gpiod_get_index(dev, "TPM IO LPCPD", 1,
+                                          GPIOD_OUT_HIGH);
+       if (IS_ERR(gpiod_lpcpd)) {
+               dev_err(&client->dev,
+                       "Failed to retrieve lpcpd-gpios from acpi.\n");
+               phy->io_lpcpd = -1;
+               /*
+                * lpcpd pin is not specified. This is not an issue as
+                * power management can be also managed by TPM specific
+                * commands. So leave with a success status code.
+                */
+               return 0;
+       }
+
+       phy->io_lpcpd = desc_to_gpio(gpiod_lpcpd);
+
+       return 0;
+}
+
 static int st33zp24_i2c_of_request_resources(struct st33zp24_i2c_phy *phy)
 {
        struct device_node *pp;
@@ -146,12 +184,6 @@ static int st33zp24_i2c_of_request_resources(struct st33zp24_i2c_phy *phy)
 
        return 0;
 }
-#else
-static int st33zp24_i2c_of_request_resources(struct st33zp24_i2c_phy *phy)
-{
-       return -ENODEV;
-}
-#endif
 
 static int st33zp24_i2c_request_resources(struct i2c_client *client,
                                          struct st33zp24_i2c_phy *phy)
@@ -221,6 +253,10 @@ static int st33zp24_i2c_probe(struct i2c_client *client,
                ret = st33zp24_i2c_request_resources(client, phy);
                if (ret)
                        return ret;
+       } else if (ACPI_HANDLE(&client->dev)) {
+               ret = st33zp24_i2c_acpi_request_resources(phy);
+               if (ret)
+                       return ret;
        }
 
        return st33zp24_probe(phy, &i2c_phy_ops, &client->dev, client->irq,
@@ -245,13 +281,17 @@ static const struct i2c_device_id st33zp24_i2c_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, st33zp24_i2c_id);
 
-#ifdef CONFIG_OF
 static const struct of_device_id of_st33zp24_i2c_match[] = {
        { .compatible = "st,st33zp24-i2c", },
        {}
 };
 MODULE_DEVICE_TABLE(of, of_st33zp24_i2c_match);
-#endif
+
+static const struct acpi_device_id st33zp24_i2c_acpi_match[] = {
+       {"SMO3324"},
+       {}
+};
+MODULE_DEVICE_TABLE(acpi, st33zp24_i2c_acpi_match);
 
 static SIMPLE_DEV_PM_OPS(st33zp24_i2c_ops, st33zp24_pm_suspend,
                         st33zp24_pm_resume);
@@ -261,6 +301,7 @@ static struct i2c_driver st33zp24_i2c_driver = {
                .name = TPM_ST33_I2C,
                .pm = &st33zp24_i2c_ops,
                .of_match_table = of_match_ptr(of_st33zp24_i2c_match),
+               .acpi_match_table = ACPI_PTR(st33zp24_i2c_acpi_match),
        },
        .probe = st33zp24_i2c_probe,
        .remove = st33zp24_i2c_remove,