On Fri, Jan 11, 2013 at 04:22:46PM -0800, Stephen Warren wrote:
On 01/11/2013 11:44 AM, Allen Martin wrote:
Add driver for tegra SPI "SLINK" style driver. This controller is similar to the tegra20 SPI "SFLASH" controller. The difference is that the SLINK controller is a genernal purpose SPI controller and the SFLASH controller is special purpose and can only talk to FLASH devices. In addition there are potentially many instances of an SLINK controller on tegra and only a single instance of SFLASH. Tegra20 is currently ths only version of tegra that instantiates an SFLASH controller.
This driver supports basic PIO mode of operation and is configurable (CONFIG_OF_CONTROL) to be driven off devicetree bindings. Up to 4 devices per controller may be attached, although typically only a single chip select line is exposed from tegra per controller so in reality this is usually limited to 1.
To enable this driver, use CONFIG_TEGRA_SLINK
diff --git a/drivers/spi/tegra_slink.c b/drivers/spi/tegra_slink.c
+void spi_init(void) +{
- int node = 0, i;
- struct tegra_spi_ctrl *ctrl;
- for (i = 0; i < CONFIG_TEGRA_SLINK_CTRLS; i++) {
ctrl = &spi_ctrls[i];+#ifdef CONFIG_OF_CONTROL
Is this ever false for Tegra upstream? I don't think so.
No, but I think it's worthwhile to keep it under #ifdef so this driver could be used from the SPL if the need ever comes up. I tested by forcing it off for this driver and it works.
node = fdtdec_next_compatible(gd->fdt_blob, node,COMPAT_NVIDIA_TEGRA20_SLINK);if (!node)break;ctrl->regs = (struct slink_tegra *)fdtdec_get_addr(gd->fdt_blob,node, "reg");if ((fdt_addr_t)ctrl->regs == FDT_ADDR_T_NONE) {debug("%s: no slink register found\n", __func__);break;Shouldn't most of the "break"s in this loop be "continue"s, so that any other nodes can be parsed? After all, this loop is trying to initialize all SLINK controllers in the DT right?
True, and looking at this code I think the driver is going to do something bad if any of the controllers are not fully specified and you go to use it later. I think the controller structure needs a "valid" flag.
-Allen