V4L/DVB (12416): radio-si470x: add i2c driver for si470x

This patch supports i2c interface of si470x. The i2c specific part
exists in radio-si470x-i2c.c file and the common part uses
radio-si470x-common.c file. The '#if defined' is inserted inevitably
because of parts used only si470x usb in the common file.

The current driver version doesn't support the RDS.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Tobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

5 files changed, 281 insertions, 0 deletions

diff --git a/drivers/media/radio/si470x/Kconfig b/drivers/media/radio/si470x/Kconfig
index 20d05c04fa27..a466654ee5c9 100644
--- a/drivers/media/radio/si470x/Kconfig
+++ b/drivers/media/radio/si470x/Kconfig
@@ -22,3 +22,16 @@ config USB_SI470X
 
           To compile this driver as a module, choose M here: the
           module will be called radio-usb-si470x.
+
+config I2C_SI470X
+        tristate "Silicon Labs Si470x FM Radio Receiver support with I2C"
+        depends on I2C && RADIO_SI470X && !USB_SI470X
+        ---help---
+          This is a driver for I2C devices with the Silicon Labs SI470x
+          chip.
+
+          Say Y here if you want to connect this type of radio to your
+          computer's I2C port.
+
+          To compile this driver as a module, choose M here: the
+          module will be called radio-i2c-si470x.
diff --git a/drivers/media/radio/si470x/Makefile b/drivers/media/radio/si470x/Makefile
index 3cb777fe36bf..06964816cfd6 100644
--- a/drivers/media/radio/si470x/Makefile
+++ b/drivers/media/radio/si470x/Makefile
@@ -3,5 +3,7 @@
 #
 
 radio-usb-si470x-objs   := radio-si470x-usb.o radio-si470x-common.o
+radio-i2c-si470x-objs   := radio-si470x-i2c.o radio-si470x-common.o
 
 obj-$(CONFIG_USB_SI470X) += radio-usb-si470x.o
+obj-$(CONFIG_I2C_SI470X) += radio-i2c-si470x.o
diff --git a/drivers/media/radio/si470x/radio-si470x-common.c b/drivers/media/radio/si470x/radio-si470x-common.c
index 9f9a417caf93..f33315f2c543 100644
--- a/drivers/media/radio/si470x/radio-si470x-common.c
+++ b/drivers/media/radio/si470x/radio-si470x-common.c
@@ -581,8 +581,12 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv,
         /* driver constants */
         strcpy(tuner->name, "FM");
         tuner->type = V4L2_TUNER_RADIO;
+#if defined(CONFIG_USB_SI470X) || defined(CONFIG_USB_SI470X_MODULE)
         tuner->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
                             V4L2_TUNER_CAP_RDS;
+#else
+        tuner->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
+#endif
 
         /* range limits */
         switch ((radio->registers[SYSCONFIG2] & SYSCONFIG2_BAND) >> 6) {
@@ -608,10 +612,12 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv,
                 tuner->rxsubchans = V4L2_TUNER_SUB_MONO;
         else
                 tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;
+#if defined(CONFIG_USB_SI470X) || defined(CONFIG_USB_SI470X_MODULE)
         /* If there is a reliable method of detecting an RDS channel,
            then this code should check for that before setting this
            RDS subchannel. */
         tuner->rxsubchans |= V4L2_TUNER_SUB_RDS;
+#endif
 
         /* mono/stereo selector */
         if ((radio->registers[POWERCFG] & POWERCFG_MONO) == 0)
diff --git a/drivers/media/radio/si470x/radio-si470x-i2c.c b/drivers/media/radio/si470x/radio-si470x-i2c.c
new file mode 100644
index 000000000000..218102184702
--- /dev/null
+++ b/drivers/media/radio/si470x/radio-si470x-i2c.c
@@ -0,0 +1,254 @@
+/*
+ * drivers/media/radio/si470x/radio-si470x-i2c.c
+ *
+ * I2C driver for radios with Silicon Labs Si470x FM Radio Receivers
+ *
+ * Copyright (C) 2009 Samsung Electronics Co.Ltd
+ * Author: Joonyoung Shim <jy0922.shim@samsung.com>
+ *
+ *  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 the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ *
+ * TODO:
+ * - RDS support
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+
+#include "radio-si470x.h"
+
+#define DRIVER_KERNEL_VERSION   KERNEL_VERSION(1, 0, 0)
+#define DRIVER_CARD             "Silicon Labs Si470x FM Radio Receiver"
+#define DRIVER_VERSION          "1.0.0"
+
+/* starting with the upper byte of register 0x0a */
+#define READ_REG_NUM            RADIO_REGISTER_NUM
+#define READ_INDEX(i)           ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
+
+static int si470x_get_all_registers(struct si470x_device *radio)
+{
+        int i;
+        u16 buf[READ_REG_NUM];
+        struct i2c_msg msgs[1] = {
+                { radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM,
+                        (void *)buf },
+        };
+
+        if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
+                return -EIO;
+
+        for (i = 0; i < READ_REG_NUM; i++)
+                radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
+
+        return 0;
+}
+
+int si470x_get_register(struct si470x_device *radio, int regnr)
+{
+        u16 buf[READ_REG_NUM];
+        struct i2c_msg msgs[1] = {
+                { radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM,
+                        (void *)buf },
+        };
+
+        if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
+                return -EIO;
+
+        radio->registers[regnr] = __be16_to_cpu(buf[READ_INDEX(regnr)]);
+
+        return 0;
+}
+
+/* starting with the upper byte of register 0x02h */
+#define WRITE_REG_NUM           8
+#define WRITE_INDEX(i)          (i + 0x02)
+
+int si470x_set_register(struct si470x_device *radio, int regnr)
+{
+        int i;
+        u16 buf[WRITE_REG_NUM];
+        struct i2c_msg msgs[1] = {
+                { radio->client->addr, 0, sizeof(u16) * WRITE_REG_NUM,
+                        (void *)buf },
+        };
+
+        for (i = 0; i < WRITE_REG_NUM; i++)
+                buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
+
+        if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
+                return -EIO;
+
+        return 0;
+}
+
+int si470x_disconnect_check(struct si470x_device *radio)
+{
+        return 0;
+}
+
+static int si470x_fops_open(struct file *file)
+{
+        struct si470x_device *radio = video_drvdata(file);
+        int retval = 0;
+
+        mutex_lock(&radio->lock);
+        radio->users++;
+
+        if (radio->users == 1)
+                /* start radio */
+                retval = si470x_start(radio);
+        mutex_unlock(&radio->lock);
+
+        return retval;
+}
+
+static int si470x_fops_release(struct file *file)
+{
+        struct si470x_device *radio = video_drvdata(file);
+        int retval = 0;
+
+        /* safety check */
+        if (!radio)
+                return -ENODEV;
+
+        mutex_lock(&radio->lock);
+        radio->users--;
+        if (radio->users == 0)
+                /* stop radio */
+                retval = si470x_stop(radio);
+        mutex_unlock(&radio->lock);
+
+        return retval;
+}
+
+const struct v4l2_file_operations si470x_fops = {
+        .owner          = THIS_MODULE,
+        .ioctl          = video_ioctl2,
+        .open           = si470x_fops_open,
+        .release        = si470x_fops_release,
+};
+
+int si470x_vidioc_querycap(struct file *file, void *priv,
+                struct v4l2_capability *capability)
+{
+        strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
+        strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
+        capability->version = DRIVER_KERNEL_VERSION;
+        capability->capabilities = V4L2_CAP_HW_FREQ_SEEK |
+                V4L2_CAP_TUNER | V4L2_CAP_RADIO;
+
+        return 0;
+}
+
+static int __devinit si470x_i2c_probe(struct i2c_client *client,
+                const struct i2c_device_id *id)
+{
+        struct si470x_device *radio;
+        int retval = 0;
+
+        /* private data allocation and initialization */
+        radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
+        if (!radio) {
+                retval = -ENOMEM;
+                goto err_initial;
+        }
+        radio->client = client;
+        radio->users = 0;
+        mutex_init(&radio->lock);
+
+        /* video device allocation and initialization */
+        radio->videodev = video_device_alloc();
+        if (!radio->videodev) {
+                retval = -ENOMEM;
+                goto err_radio;
+        }
+        memcpy(radio->videodev, &si470x_viddev_template,
+                        sizeof(si470x_viddev_template));
+        video_set_drvdata(radio->videodev, radio);
+
+        /* power up : need 110ms */
+        radio->registers[POWERCFG] = POWERCFG_ENABLE;
+        if (si470x_set_register(radio, POWERCFG) < 0) {
+                retval = -EIO;
+                goto err_all;
+        }
+        msleep(110);
+
+        /* show some infos about the specific si470x device */
+        if (si470x_get_all_registers(radio) < 0) {
+                retval = -EIO;
+                goto err_radio;
+        }
+        dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
+                        radio->registers[DEVICEID], radio->registers[CHIPID]);
+
+        /* set initial frequency */
+        si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
+
+        /* register video device */
+        retval = video_register_device(radio->videodev, VFL_TYPE_RADIO, -1);
+        if (retval) {
+                dev_warn(&client->dev, "Could not register video device\n");
+                goto err_all;
+        }
+
+        i2c_set_clientdata(client, radio);
+
+        return 0;
+err_all:
+        video_device_release(radio->videodev);
+err_radio:
+        kfree(radio);
+err_initial:
+        return retval;
+}
+
+static __devexit int si470x_i2c_remove(struct i2c_client *client)
+{
+        struct si470x_device *radio = i2c_get_clientdata(client);
+
+        video_unregister_device(radio->videodev);
+        kfree(radio);
+        i2c_set_clientdata(client, NULL);
+
+        return 0;
+}
+
+static const struct i2c_device_id si470x_i2c_id[] = {
+        { "si470x", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
+
+static struct i2c_driver si470x_i2c_driver = {
+        .driver = {
+                .name = "si470x",
+                .owner = THIS_MODULE,
+        },
+        .probe = si470x_i2c_probe,
+        .remove = __devexit_p(si470x_i2c_remove),
+        .id_table = si470x_i2c_id,
+};
+
+static int __init si470x_i2c_init(void)
+{
+        return i2c_add_driver(&si470x_i2c_driver);
+}
+module_init(si470x_i2c_init);
+
+static void __exit si470x_i2c_exit(void)
+{
+        i2c_del_driver(&si470x_i2c_driver);
+}
+module_exit(si470x_i2c_exit);
+
+MODULE_DESCRIPTION("i2c radio driver for si470x fm radio receivers");
+MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/media/radio/si470x/radio-si470x.h b/drivers/media/radio/si470x/radio-si470x.h
index d24829b04eb2..794112c759b8 100644
--- a/drivers/media/radio/si470x/radio-si470x.h
+++ b/drivers/media/radio/si470x/radio-si470x.h
@@ -143,6 +143,11 @@
 struct si470x_device {
         struct video_device *videodev;
 
+#if defined(CONFIG_I2C_SI470X) || defined(CONFIG_I2C_SI470X_MODULE)
+        struct i2c_client *client;
+#endif
+
+#if defined(CONFIG_USB_SI470X) || defined(CONFIG_USB_SI470X_MODULE)
         /* reference to USB and video device */
         struct usb_device *usbdev;
         struct usb_interface *intf;
@@ -160,6 +165,7 @@ struct si470x_device {
         /* driver management */
         unsigned char disconnected;
         struct mutex disconnect_lock;
+#endif
         unsigned int users;
 
         /* Silabs internal registers (0..15) */