MLK-21520-2 spi: lpspi: add multi SS support in PIO mode

Add "fsl,spi-num-chipselects" check to support multi SS function in PIO
mode.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 38a7a3b..b9c2347 100644 (file)
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -826,7 +826,7 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
        struct spi_imx_master *lpspi_platform_info =
                dev_get_platdata(&pdev->dev);
        struct resource *res;
-       int i, ret, irq;
+       int i, ret, irq, num_cs;
        u32 temp;
 
        if (!np && !lpspi_platform_info) {
@@ -849,6 +849,16 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
        controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
        controller->bus_num = pdev->id;
 
+       ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
+       if (ret < 0) {
+               if (lpspi_platform_info) {
+                       num_cs = lpspi_platform_info->num_chipselect;
+                       controller->num_chipselect = num_cs;
+               }
+       } else {
+               controller->num_chipselect = num_cs;
+       }
+
        fsl_lpspi = spi_controller_get_devdata(controller);
        fsl_lpspi->dev = &pdev->dev;
        dev_set_drvdata(&pdev->dev, fsl_lpspi);