i2c: pca954x: add device tree binding

No longer rely on the implicit matching with the i2c device name, use
an explicit compatible string instead.

Keep a direct pointer to the chip description instead of an index into
the chip description array.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>

diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 528e755..6dfd31b 100644 (file)
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -42,6 +42,7 @@
 #include <linux/i2c/pca954x.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/pm.h>
 #include <linux/slab.h>
 
@@ -58,14 +59,6 @@ enum pca_type {
        pca_9548,
 };
 
-struct pca954x {
-       enum pca_type type;
-
-       u8 last_chan;           /* last register value */
-       u8 deselect;
-       struct i2c_client *client;
-};
-
 struct chip_desc {
        u8 nchans;
        u8 enable;      /* used for muxes only */
@@ -75,6 +68,14 @@ struct chip_desc {
        } muxtype;
 };
 
+struct pca954x {
+       const struct chip_desc *chip;
+
+       u8 last_chan;           /* last register value */
+       u8 deselect;
+       struct i2c_client *client;
+};
+
 /* Provide specs for the PCA954x types we know about */
 static const struct chip_desc chips[] = {
        [pca_9540] = {
@@ -119,6 +120,20 @@ static const struct i2c_device_id pca954x_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, pca954x_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id pca954x_of_match[] = {
+       { .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
+       { .compatible = "nxp,pca9542", .data = &chips[pca_9542] },
+       { .compatible = "nxp,pca9543", .data = &chips[pca_9543] },
+       { .compatible = "nxp,pca9544", .data = &chips[pca_9544] },
+       { .compatible = "nxp,pca9545", .data = &chips[pca_9545] },
+       { .compatible = "nxp,pca9546", .data = &chips[pca_9546] },
+       { .compatible = "nxp,pca9547", .data = &chips[pca_9547] },
+       { .compatible = "nxp,pca9548", .data = &chips[pca_9548] },
+       {}
+};
+#endif
+
 /* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer()
    for this as they will try to lock adapter a second time */
 static int pca954x_reg_write(struct i2c_adapter *adap,
@@ -151,7 +166,7 @@ static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
 {
        struct pca954x *data = i2c_mux_priv(muxc);
        struct i2c_client *client = data->client;
-       const struct chip_desc *chip = &chips[data->type];
+       const struct chip_desc *chip = data->chip;
        u8 regval;
        int ret = 0;
 
@@ -197,6 +212,7 @@ static int pca954x_probe(struct i2c_client *client,
        int num, force, class;
        struct i2c_mux_core *muxc;
        struct pca954x *data;
+       const struct of_device_id *match;
        int ret;
 
        if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
@@ -226,14 +242,19 @@ static int pca954x_probe(struct i2c_client *client,
                return -ENODEV;
        }
 
-       data->type = id->driver_data;
+       match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
+       if (match)
+               data->chip = of_device_get_match_data(&client->dev);
+       else
+               data->chip = &chips[id->driver_data];
+
        data->last_chan = 0;               /* force the first selection */
 
        idle_disconnect_dt = of_node &&
                of_property_read_bool(of_node, "i2c-mux-idle-disconnect");
 
        /* Now create an adapter for each channel */
-       for (num = 0; num < chips[data->type].nchans; num++) {
+       for (num = 0; num < data->chip->nchans; num++) {
                bool idle_disconnect_pd = false;
 
                force = 0;                        /* dynamic adap number */
@@ -263,7 +284,7 @@ static int pca954x_probe(struct i2c_client *client,
 
        dev_info(&client->dev,
                 "registered %d multiplexed busses for I2C %s %s\n",
-                num, chips[data->type].muxtype == pca954x_ismux
+                num, data->chip->muxtype == pca954x_ismux
                                ? "mux" : "switch", client->name);
 
        return 0;
@@ -299,6 +320,7 @@ static struct i2c_driver pca954x_driver = {
        .driver         = {
                .name   = "pca954x",
                .pm     = &pca954x_pm,
+               .of_match_table = of_match_ptr(pca954x_of_match),
        },
        .probe          = pca954x_probe,
        .remove         = pca954x_remove,