NFC: pn544: i2c: Add device-tree (Open Firmware) support to PN544

Add functions to recover hardware resources from the device-tree when not
provided by the platform data.

Signed-off-by: Clément Perrochaud <clement.perrochaud@nxp.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 131 insertions, 17 deletions

diff --git a/drivers/nfc/pn544/i2c.c b/drivers/nfc/pn544/i2c.c
index f2acd85be86e..5239e3b54120 100644
--- a/drivers/nfc/pn544/i2c.c
+++ b/drivers/nfc/pn544/i2c.c
@@ -22,6 +22,8 @@
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/of_irq.h>
 #include <linux/miscdevice.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
@@ -857,6 +859,92 @@ exit_state_wait_secure_write_answer:
         }
 }
 
+#ifdef CONFIG_OF
+
+static int pn544_hci_i2c_of_request_resources(struct i2c_client *client)
+{
+        struct pn544_i2c_phy *phy = i2c_get_clientdata(client);
+        struct device_node *pp;
+        int ret;
+
+        pp = client->dev.of_node;
+        if (!pp) {
+                ret = -ENODEV;
+                goto err_dt;
+        }
+
+        /* Obtention of EN GPIO from device tree */
+        ret = of_get_named_gpio(pp, "enable-gpios", 0);
+        if (ret < 0) {
+                if (ret != -EPROBE_DEFER)
+                        nfc_err(&client->dev,
+                                "Failed to get EN gpio, error: %d\n", ret);
+                goto err_dt;
+        }
+        phy->gpio_en = ret;
+
+        /* Configuration of EN GPIO */
+        ret = gpio_request(phy->gpio_en, "pn544_en");
+        if (ret) {
+                nfc_err(&client->dev, "Fail EN pin\n");
+                goto err_dt;
+        }
+        ret = gpio_direction_output(phy->gpio_en, 0);
+        if (ret) {
+                nfc_err(&client->dev, "Fail EN pin direction\n");
+                goto err_gpio_en;
+        }
+
+        /* Obtention of FW GPIO from device tree */
+        ret = of_get_named_gpio(pp, "firmware-gpios", 0);
+        if (ret < 0) {
+                if (ret != -EPROBE_DEFER)
+                        nfc_err(&client->dev,
+                                "Failed to get FW gpio, error: %d\n", ret);
+                goto err_gpio_en;
+        }
+        phy->gpio_fw = ret;
+
+        /* Configuration of FW GPIO */
+        ret = gpio_request(phy->gpio_fw, "pn544_fw");
+        if (ret) {
+                nfc_err(&client->dev, "Fail FW pin\n");
+                goto err_gpio_en;
+        }
+        ret = gpio_direction_output(phy->gpio_fw, 0);
+        if (ret) {
+                nfc_err(&client->dev, "Fail FW pin direction\n");
+                goto err_gpio_fw;
+        }
+
+        /* IRQ */
+        ret = irq_of_parse_and_map(pp, 0);
+        if (ret < 0) {
+                nfc_err(&client->dev,
+                        "Unable to get irq, error: %d\n", ret);
+                goto err_gpio_fw;
+        }
+        client->irq = ret;
+
+        return 0;
+
+err_gpio_fw:
+        gpio_free(phy->gpio_fw);
+err_gpio_en:
+        gpio_free(phy->gpio_en);
+err_dt:
+        return ret;
+}
+
+#else
+
+static int pn544_hci_i2c_of_request_resources(struct i2c_client *client)
+{
+        return -ENODEV;
+}
+
+#endif
+
 static int pn544_hci_i2c_probe(struct i2c_client *client,
                                const struct i2c_device_id *id)
 {
@@ -887,25 +975,36 @@ static int pn544_hci_i2c_probe(struct i2c_client *client,
         i2c_set_clientdata(client, phy);
 
         pdata = client->dev.platform_data;
-        if (pdata == NULL) {
-                nfc_err(&client->dev, "No platform data\n");
-                return -EINVAL;
-        }
 
-        if (pdata->request_resources == NULL) {
-                nfc_err(&client->dev, "request_resources() missing\n");
-                return -EINVAL;
-        }
+        /* No platform data, using device tree. */
+        if (!pdata && client->dev.of_node) {
+                r = pn544_hci_i2c_of_request_resources(client);
+                if (r) {
+                        nfc_err(&client->dev, "No DT data\n");
+                        return r;
+                }
+        /* Using platform data. */
+        } else if (pdata) {
 
-        r = pdata->request_resources(client);
-        if (r) {
-                nfc_err(&client->dev, "Cannot get platform resources\n");
-                return r;
-        }
+                if (pdata->request_resources == NULL) {
+                        nfc_err(&client->dev, "request_resources() missing\n");
+                        return -EINVAL;
+                }
+
+                r = pdata->request_resources(client);
+                if (r) {
+                        nfc_err(&client->dev,
+                                "Cannot get platform resources\n");
+                        return r;
+                }
 
-        phy->gpio_en = pdata->get_gpio(NFC_GPIO_ENABLE);
-        phy->gpio_fw = pdata->get_gpio(NFC_GPIO_FW_RESET);
-        phy->gpio_irq = pdata->get_gpio(NFC_GPIO_IRQ);
+                phy->gpio_en = pdata->get_gpio(NFC_GPIO_ENABLE);
+                phy->gpio_fw = pdata->get_gpio(NFC_GPIO_FW_RESET);
+                phy->gpio_irq = pdata->get_gpio(NFC_GPIO_IRQ);
+        } else {
+                nfc_err(&client->dev, "No platform data\n");
+                return -EINVAL;
+        }
 
         pn544_hci_i2c_platform_init(phy);
 
@@ -953,15 +1052,30 @@ static int pn544_hci_i2c_remove(struct i2c_client *client)
                 pn544_hci_i2c_disable(phy);
 
         free_irq(client->irq, phy);
-        if (pdata->free_resources)
+
+        /* No platform data, GPIOs have been requested by this driver */
+        if (!pdata) {
+                gpio_free(phy->gpio_en);
+                gpio_free(phy->gpio_fw);
+        /* Using platform data */
+        } else if (pdata->free_resources) {
                 pdata->free_resources();
+        }
 
         return 0;
 }
 
+static const struct of_device_id of_pn544_i2c_match[] = {
+        { .compatible = "nxp,pn544-i2c", },
+        {},
+};
+MODULE_DEVICE_TABLE(of, of_pn544_i2c_match);
+
 static struct i2c_driver pn544_hci_i2c_driver = {
         .driver = {
                    .name = PN544_HCI_I2C_DRIVER_NAME,
+                   .owner  = THIS_MODULE,
+                   .of_match_table = of_match_ptr(of_pn544_i2c_match),
                   },
         .probe = pn544_hci_i2c_probe,
         .id_table = pn544_hci_i2c_id_table,