[coreboot-gerrit] Change in ...coreboot[master]: mediatek: Support GPIO based SPI CS

[You-Cheng Syu (Code Review)]

You-Cheng Syu has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/33165

Change subject: mediatek: Support GPIO based SPI CS
......................................................................

mediatek: Support GPIO based SPI CS

In some cases we might want to use GPIO based SPI CS. When using GPIO
based SPI CS, we need to manually make CS low/high before/after SPI
transactions.

BUG=b:132311067
TEST=Verified that b/132311067 is irreproducible now.

Change-Id: I61653fb19242b6ee6be9a45545a8b66e5c9c7cad
---
M src/soc/mediatek/common/include/soc/spi_common.h
M src/soc/mediatek/common/spi.c
2 files changed, 12 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/65/33165/1

diff --git a/src/soc/mediatek/common/include/soc/spi_common.h b/src/soc/mediatek/common/include/soc/spi_common.h
index 162db59..2e87720 100644
--- a/src/soc/mediatek/common/include/soc/spi_common.h
+++ b/src/soc/mediatek/common/include/soc/spi_common.h
@@ -16,6 +16,7 @@
 #ifndef MTK_COMMON_SPI_H
 #define MTK_COMMON_SPI_H

+#include <soc/gpio_base.h>
 #include <spi-generic.h>

enum {
@@ -77,6 +78,7 @@
    struct mtk_spi_regs *regs;
    int initialized;
    int state;
+	gpio_t *cs_gpio;
 };

extern const struct spi_ctrlr spi_ctrlr;
diff --git a/src/soc/mediatek/common/spi.c b/src/soc/mediatek/common/spi.c
index 71ed95a..c8aadbf 100644
--- a/src/soc/mediatek/common/spi.c
+++ b/src/soc/mediatek/common/spi.c
@@ -17,6 +17,7 @@
 #include <assert.h>
 #include <console/console.h>
 #include <endian.h>
+#include <gpio.h>
 #include <stdlib.h>
 #include <soc/pll.h>
 #include <soc/spi.h>
@@ -87,6 +88,9 @@

clrsetbits_le32(&regs->spi_pad_macro_sel_reg, SPI_PAD_SEL_MASK,
    		pad_select);
+
+	if (slave->cs_gpio != NULL)
+		gpio_output(*slave->cs_gpio, 1);
 }

static void mtk_spi_dump_data(const char *name, const uint8_t *data, int size)
@@ -109,6 +113,9 @@
    setbits_le32(&regs->spi_cmd_reg, 1 << SPI_CMD_PAUSE_EN_SHIFT);
    mtk_slave->state = MTK_SPI_IDLE;

+	if (mtk_slave->cs_gpio != NULL)
+		gpio_output(*mtk_slave->cs_gpio, 0);
+
    return 0;
 }

@@ -243,6 +250,9 @@
    clrbits_le32(&regs->spi_cmd_reg, SPI_CMD_PAUSE_EN);
    spi_sw_reset(regs);
    mtk_slave->state = MTK_SPI_IDLE;
+
+	if (mtk_slave->cs_gpio != NULL)
+		gpio_output(*mtk_slave->cs_gpio, 1);
 }

static int spi_ctrlr_setup(const struct spi_slave *slave)