Add hotplug support to mcp251x driver

Chip model can now be selected directly by matching the modalias name
(instead of filling the .model field in platform_data), and allows the
module to be auto-loaded. Previous behaviour is of course still supported.

Convert the two in-tree users to this feature (icontrol & zeus).
Tested on an Zeus platform (mcp2515).

Signed-off-by: Marc Zyngier <maz@misterjones.org>
Acked-by: Christian Pellegrin <chripell@fsfe.org>
Cc: Edwin Peer <epeer@tmtservices.co.za>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 21 insertions, 10 deletions

diff --git a/arch/arm/mach-pxa/icontrol.c b/arch/arm/mach-pxa/icontrol.c
index 771137fc1a82..5ccb0ceff6c4 100644
--- a/arch/arm/mach-pxa/icontrol.c
+++ b/arch/arm/mach-pxa/icontrol.c
@@ -73,7 +73,6 @@ static struct pxa2xx_spi_chip mcp251x_chip_info4 = {
 
 static struct mcp251x_platform_data mcp251x_info = {
         .oscillator_frequency = 16E6,
-        .model                = CAN_MCP251X_MCP2515,
         .board_specific_setup = NULL,
         .power_enable         = NULL,
         .transceiver_enable   = NULL
@@ -81,7 +80,7 @@ static struct mcp251x_platform_data mcp251x_info = {
 
 static struct spi_board_info mcp251x_board_info[] = {
         {
-                .modalias        = "mcp251x",
+                .modalias        = "mcp2515",
                 .max_speed_hz    = 6500000,
                 .bus_num         = 3,
                 .chip_select     = 0,
@@ -90,7 +89,7 @@ static struct spi_board_info mcp251x_board_info[] = {
                 .irq             = gpio_to_irq(ICONTROL_MCP251x_nIRQ1)
         },
         {
-                .modalias        = "mcp251x",
+                .modalias        = "mcp2515",
                 .max_speed_hz    = 6500000,
                 .bus_num         = 3,
                 .chip_select     = 1,
@@ -99,7 +98,7 @@ static struct spi_board_info mcp251x_board_info[] = {
                 .irq             = gpio_to_irq(ICONTROL_MCP251x_nIRQ2)
         },
         {
-                .modalias        = "mcp251x",
+                .modalias        = "mcp2515",
                 .max_speed_hz    = 6500000,
                 .bus_num         = 4,
                 .chip_select     = 0,
@@ -108,7 +107,7 @@ static struct spi_board_info mcp251x_board_info[] = {
                 .irq             = gpio_to_irq(ICONTROL_MCP251x_nIRQ3)
         },
         {
-                .modalias        = "mcp251x",
+                .modalias        = "mcp2515",
                 .max_speed_hz    = 6500000,
                 .bus_num         = 4,
                 .chip_select     = 1,
diff --git a/arch/arm/mach-pxa/zeus.c b/arch/arm/mach-pxa/zeus.c
index 39896d883584..dbd256966379 100644
--- a/arch/arm/mach-pxa/zeus.c
+++ b/arch/arm/mach-pxa/zeus.c
@@ -414,15 +414,13 @@ static int zeus_mcp2515_transceiver_enable(int enable)
 
 static struct mcp251x_platform_data zeus_mcp2515_pdata = {
         .oscillator_frequency   = 16*1000*1000,
-        .model                  = CAN_MCP251X_MCP2515,
         .board_specific_setup   = zeus_mcp2515_setup,
-        .transceiver_enable     = zeus_mcp2515_transceiver_enable,
         .power_enable           = zeus_mcp2515_transceiver_enable,
 };
 
 static struct spi_board_info zeus_spi_board_info[] = {
         [0] = {
-                .modalias       = "mcp251x",
+                .modalias       = "mcp2515",
                 .platform_data  = &zeus_mcp2515_pdata,
                 .irq            = gpio_to_irq(ZEUS_CAN_GPIO),
                 .max_speed_hz   = 1*1000*1000,
diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c
index f8cc168ec76c..f521579f5adb 100644
--- a/drivers/net/can/mcp251x.c
+++ b/drivers/net/can/mcp251x.c
@@ -922,12 +922,16 @@ static int __devinit mcp251x_can_probe(struct spi_device *spi)
         struct net_device *net;
         struct mcp251x_priv *priv;
         struct mcp251x_platform_data *pdata = spi->dev.platform_data;
+        int model = spi_get_device_id(spi)->driver_data;
         int ret = -ENODEV;
 
         if (!pdata)
                 /* Platform data is required for osc freq */
                 goto error_out;
 
+        if (model)
+                pdata->model = model;
+
         /* Allocate can/net device */
         net = alloc_candev(sizeof(struct mcp251x_priv), TX_ECHO_SKB_MAX);
         if (!net) {
@@ -1117,6 +1121,15 @@ static int mcp251x_can_resume(struct spi_device *spi)
 #define mcp251x_can_resume NULL
 #endif
 
+static struct spi_device_id mcp251x_id_table[] = {
+        { "mcp251x",    0 /* Use pdata.model */ },
+        { "mcp2510",    CAN_MCP251X_MCP2510 },
+        { "mcp2515",    CAN_MCP251X_MCP2515 },
+        { },
+};
+
+MODULE_DEVICE_TABLE(spi, mcp251x_id_table);
+
 static struct spi_driver mcp251x_can_driver = {
         .driver = {
                 .name = DEVICE_NAME,
@@ -1124,6 +1137,7 @@ static struct spi_driver mcp251x_can_driver = {
                 .owner = THIS_MODULE,
         },
 
+        .id_table = mcp251x_id_table,
         .probe = mcp251x_can_probe,
         .remove = __devexit_p(mcp251x_can_remove),
         .suspend = mcp251x_can_suspend,
diff --git a/include/linux/can/platform/mcp251x.h b/include/linux/can/platform/mcp251x.h
index 1448177d86d5..dba28268e651 100644
--- a/include/linux/can/platform/mcp251x.h
+++ b/include/linux/can/platform/mcp251x.h
@@ -26,8 +26,8 @@
 struct mcp251x_platform_data {
         unsigned long oscillator_frequency;
         int model;
-#define CAN_MCP251X_MCP2510 0
-#define CAN_MCP251X_MCP2515 1
+#define CAN_MCP251X_MCP2510 0x2510
+#define CAN_MCP251X_MCP2515 0x2515
         int (*board_specific_setup)(struct spi_device *spi);
         int (*transceiver_enable)(int enable);
         int (*power_enable) (int enable);