can: mcp251x: Add device tree support

This patch adds Device Tree support to the Microchip MCP251X driver.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/Documentation/devicetree/bindings/net/can/microchip,mcp251x.txt b/Documentation/devicetree/bindings/net/can/microchip,mcp251x.txt
new file mode 100644 (file)
index 0000000..ee3723b
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/can/microchip,mcp251x.txt
@@ -0,0 +1,25 @@
+* Microchip MCP251X stand-alone CAN controller device tree bindings
+
+Required properties:
+ - compatible: Should be one of the following:
+   - "microchip,mcp2510" for MCP2510.
+   - "microchip,mcp2515" for MCP2515.
+ - reg: SPI chip select.
+ - clocks: The clock feeding the CAN controller.
+ - interrupt-parent: The parent interrupt controller.
+ - interrupts: Should contain IRQ line for the CAN controller.
+
+Optional properties:
+ - vdd-supply: Regulator that powers the CAN controller.
+ - xceiver-supply: Regulator that powers the CAN transceiver.
+
+Example:
+       can0: can@1 {
+               compatible = "microchip,mcp2515";
+               reg = <1>;
+               clocks = <&clk24m>;
+               interrupt-parent = <&gpio4>;
+               interrupts = <13 0x2>;
+               vdd-supply = <&reg5v0>;
+               xceiver-supply = <&reg5v0>;
+       };

diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c
index 88d3877b62770702419ffba079b118b8124459b7..cdb9808d12dbc9883250ccceb5ac156be6a4c84d 100644 (file)
--- a/drivers/net/can/mcp251x.c
+++ b/drivers/net/can/mcp251x.c
@@ -58,6 +58,7 @@
 #include <linux/can/dev.h>
 #include <linux/can/led.h>
 #include <linux/can/platform/mcp251x.h>
+#include <linux/clk.h>
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/device.h>
@@ -68,6 +69,8 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/spi/spi.h>
@@ -263,6 +266,7 @@ struct mcp251x_priv {
        int restart_tx;
        struct regulator *power;
        struct regulator *transceiver;
+       struct clk *clk;
 };
 
 #define MCP251X_IS(_model) \
@@ -994,22 +998,65 @@ static const struct net_device_ops mcp251x_netdev_ops = {
        .ndo_start_xmit = mcp251x_hard_start_xmit,
 };
 
+static const struct of_device_id mcp251x_of_match[] = {
+       {
+               .compatible     = "microchip,mcp2510",
+               .data           = (void *)CAN_MCP251X_MCP2510,
+       },
+       {
+               .compatible     = "microchip,mcp2515",
+               .data           = (void *)CAN_MCP251X_MCP2515,
+       },
+       { }
+};
+MODULE_DEVICE_TABLE(of, mcp251x_of_match);
+
+static const struct spi_device_id mcp251x_id_table[] = {
+       {
+               .name           = "mcp2510",
+               .driver_data    = (kernel_ulong_t)CAN_MCP251X_MCP2510,
+       },
+       {
+               .name           = "mcp2515",
+               .driver_data    = (kernel_ulong_t)CAN_MCP251X_MCP2515,
+       },
+       { }
+};
+MODULE_DEVICE_TABLE(spi, mcp251x_id_table);
+
 static int mcp251x_can_probe(struct spi_device *spi)
 {
+       const struct of_device_id *of_id = of_match_device(mcp251x_of_match,
+                                                          &spi->dev);
+       struct mcp251x_platform_data *pdata = dev_get_platdata(&spi->dev);
        struct net_device *net;
        struct mcp251x_priv *priv;
-       struct mcp251x_platform_data *pdata = dev_get_platdata(&spi->dev);
-       int ret = -ENODEV;
+       int freq, ret = -ENODEV;
+       struct clk *clk;
+
+       clk = devm_clk_get(&spi->dev, NULL);
+       if (IS_ERR(clk)) {
+               if (pdata)
+                       freq = pdata->oscillator_frequency;
+               else
+                       return PTR_ERR(clk);
+       } else {
+               freq = clk_get_rate(clk);
+       }
 
-       if (!pdata)
-               /* Platform data is required for osc freq */
-               goto error_out;
+       /* Sanity check */
+       if (freq < 1000000 || freq > 25000000)
+               return -ERANGE;
 
        /* Allocate can/net device */
        net = alloc_candev(sizeof(struct mcp251x_priv), TX_ECHO_SKB_MAX);
-       if (!net) {
-               ret = -ENOMEM;
-               goto error_alloc;
+       if (!net)
+               return -ENOMEM;
+
+       if (!IS_ERR(clk)) {
+               ret = clk_prepare_enable(clk);
+               if (ret)
+                       goto out_free;
        }
 
        net->netdev_ops = &mcp251x_netdev_ops;
@@ -1018,23 +1065,27 @@ static int mcp251x_can_probe(struct spi_device *spi)
        priv = netdev_priv(net);
        priv->can.bittiming_const = &mcp251x_bittiming_const;
        priv->can.do_set_mode = mcp251x_do_set_mode;
-       priv->can.clock.freq = pdata->oscillator_frequency / 2;
+       priv->can.clock.freq = freq / 2;
        priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
                CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY;
-       priv->model = spi_get_device_id(spi)->driver_data;
+       if (of_id)
+               priv->model = (enum mcp251x_model)of_id->data;
+       else
+               priv->model = spi_get_device_id(spi)->driver_data;
        priv->net = net;
+       priv->clk = clk;
 
        priv->power = devm_regulator_get(&spi->dev, "vdd");
        priv->transceiver = devm_regulator_get(&spi->dev, "xceiver");
        if ((PTR_ERR(priv->power) == -EPROBE_DEFER) ||
            (PTR_ERR(priv->transceiver) == -EPROBE_DEFER)) {
                ret = -EPROBE_DEFER;
-               goto error_power;
+               goto out_clk;
        }
 
        ret = mcp251x_power_enable(priv->power, 1);
        if (ret)
-               goto error_power;
+               goto out_clk;
 
        spi_set_drvdata(spi, priv);
 
@@ -1113,11 +1164,14 @@ error_probe:
                dma_free_coherent(&spi->dev, PAGE_SIZE,
                                  priv->spi_tx_buf, priv->spi_tx_dma);
        mcp251x_power_enable(priv->power, 0);
-error_power:
+
+out_clk:
+       if (!IS_ERR(clk))
+               clk_disable_unprepare(clk);
+
+out_free:
        free_candev(net);
-error_alloc:
-       dev_err(&spi->dev, "probe failed\n");
-error_out:
+
        return ret;
 }
 
@@ -1135,6 +1189,9 @@ static int mcp251x_can_remove(struct spi_device *spi)
 
        mcp251x_power_enable(priv->power, 0);
 
+       if (!IS_ERR(priv->clk))
+               clk_disable_unprepare(priv->clk);
+
        free_candev(net);
 
        return 0;
@@ -1197,21 +1254,13 @@ static int mcp251x_can_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(mcp251x_can_pm_ops, mcp251x_can_suspend,
        mcp251x_can_resume);
 
-static const struct spi_device_id mcp251x_id_table[] = {
-       { "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,
                .owner = THIS_MODULE,
+               .of_match_table = mcp251x_of_match,
                .pm = &mcp251x_can_pm_ops,
        },
-
        .id_table = mcp251x_id_table,
        .probe = mcp251x_can_probe,
        .remove = mcp251x_can_remove,