Re: [PATCH 1/2 v2] spi: s3c64xx: use "cs-gpios" from spi node instead of "cs-gpio"

Hello Tomasz,

On 11 June 2014 01:19, Tomasz Figa [off-list ref] wrote:

Hi Naveen,

On 10.06.2014 12:08, Naveen Krishna Chatradhi wrote:

quoted

Currently, spi-s3c64xx.c needs "cs-gpio" chip select GPIO to be
defined under "controller-data" node under each slave node.

[snip]

quoted

@@ -85,6 +83,7 @@ Example:
              #size-cells = <0>;
              pinctrl-names = "default";
              pinctrl-0 = <&spi0_bus>;
+             cs-gpios = <&gpa2 5 1 0 3>;

While at it, you might also update the example to something more
appropriate on Samsung platforms, e.g. <&gpa2 5 0>;

Sylwester gave this comment, will club with the other changes.

quoted

              w25q80bw@0 {
                      #address-cells = <1>;

[snip]

quoted

+static struct s3c64xx_spi_csinfo *s3c64xx_get_cs_gpios(struct spi_device *spi)
+{
+     struct device_node *parent_np = NULL;
+     struct s3c64xx_spi_driver_data *sdd;
+     struct s3c64xx_spi_csinfo *cs;
+
+     parent_np = of_get_parent(spi->dev.of_node);
+     if (!parent_np) {
+             dev_err(&spi->dev, "Parent node not found\n");
              return ERR_PTR(-EINVAL);
      }

+     sdd = spi_master_get_devdata(spi->master);
+
      cs = kzalloc(sizeof(*cs), GFP_KERNEL);
      if (!cs) {
-             of_node_put(data_np);
+             of_node_put(parent_np);
              return ERR_PTR(-ENOMEM);
      }

      /* The CS line is asserted/deasserted by the gpio pin */
      if (sdd->cs_gpio)
-             cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
+             cs->line = of_get_named_gpio(parent_np, "cs-gpios", 0);

This is wrong. The "cs-gpios" property is supposed to be an array,
indexed by chip select number of SPI devices (indicated by their "reg"
properties).

Moreover, is there a need to parse this manually in this driver? I can
see respective parsing code in of_spi_register_master().

Right, spi_add_device() parses the "cs-gpios" and gives the "spi->cs_gpio"
before calling the driver setup() function.

Will respin with appropriate changes.

Best regards,
Tomasz

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(: Nav :)