spi/of: Create new device registration method and accessors

Dynamically inserting spi device nodes requires the use of a single
device registration method. Refactor the existing
of_register_spi_devices() to split out the core functionality for a
single device into a separate function; of_register_spi_device(). This
function will be used by the OF_DYNAMIC overlay code to make live
modifications to the tree.

Methods to lookup a device/master using a device node are added
as well, of_find_spi_master_by_node() & of_find_spi_device_by_node().

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely] Split patch into two pieces for clarity
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: <linux-spi@vger.kernel.org>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index ebcb33df2eb22facb58cebc10277c3ab12925a42..a3557c57d4f794334726398193d419fa1ca5f9ab 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1220,6 +1220,121 @@ err_init_queue:
 /*-------------------------------------------------------------------------*/
 
 #if defined(CONFIG_OF)
+static struct spi_device *
+of_register_spi_device(struct spi_master *master, struct device_node *nc)
+{
+       struct spi_device *spi;
+       int rc;
+       u32 value;
+
+       /* Alloc an spi_device */
+       spi = spi_alloc_device(master);
+       if (!spi) {
+               dev_err(&master->dev, "spi_device alloc error for %s\n",
+                       nc->full_name);
+               rc = -ENOMEM;
+               goto err_out;
+       }
+
+       /* Select device driver */
+       rc = of_modalias_node(nc, spi->modalias,
+                               sizeof(spi->modalias));
+       if (rc < 0) {
+               dev_err(&master->dev, "cannot find modalias for %s\n",
+                       nc->full_name);
+               goto err_out;
+       }
+
+       /* Device address */
+       rc = of_property_read_u32(nc, "reg", &value);
+       if (rc) {
+               dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
+                       nc->full_name, rc);
+               goto err_out;
+       }
+       spi->chip_select = value;
+
+       /* Mode (clock phase/polarity/etc.) */
+       if (of_find_property(nc, "spi-cpha", NULL))
+               spi->mode |= SPI_CPHA;
+       if (of_find_property(nc, "spi-cpol", NULL))
+               spi->mode |= SPI_CPOL;
+       if (of_find_property(nc, "spi-cs-high", NULL))
+               spi->mode |= SPI_CS_HIGH;
+       if (of_find_property(nc, "spi-3wire", NULL))
+               spi->mode |= SPI_3WIRE;
+       if (of_find_property(nc, "spi-lsb-first", NULL))
+               spi->mode |= SPI_LSB_FIRST;
+
+       /* Device DUAL/QUAD mode */
+       if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) {
+               switch (value) {
+               case 1:
+                       break;
+               case 2:
+                       spi->mode |= SPI_TX_DUAL;
+                       break;
+               case 4:
+                       spi->mode |= SPI_TX_QUAD;
+                       break;
+               default:
+                       dev_warn(&master->dev,
+                               "spi-tx-bus-width %d not supported\n",
+                               value);
+                       break;
+               }
+       }
+
+       if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) {
+               switch (value) {
+               case 1:
+                       break;
+               case 2:
+                       spi->mode |= SPI_RX_DUAL;
+                       break;
+               case 4:
+                       spi->mode |= SPI_RX_QUAD;
+                       break;
+               default:
+                       dev_warn(&master->dev,
+                               "spi-rx-bus-width %d not supported\n",
+                               value);
+                       break;
+               }
+       }
+
+       /* Device speed */
+       rc = of_property_read_u32(nc, "spi-max-frequency", &value);
+       if (rc) {
+               dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n",
+                       nc->full_name, rc);
+               goto err_out;
+       }
+       spi->max_speed_hz = value;
+
+       /* IRQ */
+       spi->irq = irq_of_parse_and_map(nc, 0);
+
+       /* Store a pointer to the node in the device structure */
+       of_node_get(nc);
+       spi->dev.of_node = nc;
+
+       /* Register the new device */
+       request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias);
+       rc = spi_add_device(spi);
+       if (rc) {
+               dev_err(&master->dev, "spi_device register error %s\n",
+                       nc->full_name);
+               goto err_out;
+       }
+
+       return spi;
+
+err_out:
+       spi_dev_put(spi);
+       return ERR_PTR(rc);
+}
+
 /**
  * of_register_spi_devices() - Register child devices onto the SPI bus
  * @master:    Pointer to spi_master device
@@ -1231,116 +1346,15 @@ static void of_register_spi_devices(struct spi_master *master)
 {
        struct spi_device *spi;
        struct device_node *nc;
-       int rc;
-       u32 value;
 
        if (!master->dev.of_node)
                return;
 
        for_each_available_child_of_node(master->dev.of_node, nc) {
-               /* Alloc an spi_device */
-               spi = spi_alloc_device(master);
-               if (!spi) {
-                       dev_err(&master->dev, "spi_device alloc error for %s\n",
+               spi = of_register_spi_device(master, nc);
+               if (IS_ERR(spi))
+                       dev_warn(&master->dev, "Failed to create SPI device for %s\n",
                                nc->full_name);
-                       spi_dev_put(spi);
-                       continue;
-               }
-
-               /* Select device driver */
-               if (of_modalias_node(nc, spi->modalias,
-                                    sizeof(spi->modalias)) < 0) {
-                       dev_err(&master->dev, "cannot find modalias for %s\n",
-                               nc->full_name);
-                       spi_dev_put(spi);
-                       continue;
-               }
-
-               /* Device address */
-               rc = of_property_read_u32(nc, "reg", &value);
-               if (rc) {
-                       dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
-                               nc->full_name, rc);
-                       spi_dev_put(spi);
-                       continue;
-               }
-               spi->chip_select = value;
-
-               /* Mode (clock phase/polarity/etc.) */
-               if (of_find_property(nc, "spi-cpha", NULL))
-                       spi->mode |= SPI_CPHA;
-               if (of_find_property(nc, "spi-cpol", NULL))
-                       spi->mode |= SPI_CPOL;
-               if (of_find_property(nc, "spi-cs-high", NULL))
-                       spi->mode |= SPI_CS_HIGH;
-               if (of_find_property(nc, "spi-3wire", NULL))
-                       spi->mode |= SPI_3WIRE;
-               if (of_find_property(nc, "spi-lsb-first", NULL))
-                       spi->mode |= SPI_LSB_FIRST;
-
-               /* Device DUAL/QUAD mode */
-               if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) {
-                       switch (value) {
-                       case 1:
-                               break;
-                       case 2:
-                               spi->mode |= SPI_TX_DUAL;
-                               break;
-                       case 4:
-                               spi->mode |= SPI_TX_QUAD;
-                               break;
-                       default:
-                               dev_warn(&master->dev,
-                                        "spi-tx-bus-width %d not supported\n",
-                                        value);
-                               break;
-                       }
-               }
-
-               if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) {
-                       switch (value) {
-                       case 1:
-                               break;
-                       case 2:
-                               spi->mode |= SPI_RX_DUAL;
-                               break;
-                       case 4:
-                               spi->mode |= SPI_RX_QUAD;
-                               break;
-                       default:
-                               dev_warn(&master->dev,
-                                        "spi-rx-bus-width %d not supported\n",
-                                        value);
-                               break;
-                       }
-               }
-
-               /* Device speed */
-               rc = of_property_read_u32(nc, "spi-max-frequency", &value);
-               if (rc) {
-                       dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n",
-                               nc->full_name, rc);
-                       spi_dev_put(spi);
-                       continue;
-               }
-               spi->max_speed_hz = value;
-
-               /* IRQ */
-               spi->irq = irq_of_parse_and_map(nc, 0);
-
-               /* Store a pointer to the node in the device structure */
-               of_node_get(nc);
-               spi->dev.of_node = nc;
-
-               /* Register the new device */
-               request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias);
-               rc = spi_add_device(spi);
-               if (rc) {
-                       dev_err(&master->dev, "spi_device register error %s\n",
-                               nc->full_name);
-                       spi_dev_put(spi);
-               }
-
        }
 }
 #else