[U-Boot] [PATCH v1 07/11] spi: stm32_qspi: Add chip select management

[Patrice Chotard]

From: Christophe Kerello <christophe.kerello at st.com>

Quad-SPI interface is able to manage 2 spi nor devices.
FSEL bit selects the flash memory to be addressed in single flash mode.

Signed-off-by: Christophe Kerello <christophe.kerello at st.com>
Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
---

 drivers/spi/stm32_qspi.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/spi/stm32_qspi.c b/drivers/spi/stm32_qspi.c
index 46915194f034..48b4dbce402b 100644
--- a/drivers/spi/stm32_qspi.c
+++ b/drivers/spi/stm32_qspi.c
@@ -160,6 +160,8 @@ enum STM32_QSPI_CCR_FMODE {
 #define STM32_CMD_READ_QUAD_OUTPUT_FAST	0x6b
 #define STM32_CMD_QUAD_PP		0x32
 
+#define STM32_MAX_NORCHIP 2
+
 struct stm32_qspi_platdata {
 	u32 base;
 	u32 memory_map;
@@ -217,6 +219,12 @@ static void _stm32_qspi_set_flash_size(struct stm32_qspi_priv *priv, u32 size)
 			fsize << STM32_QSPI_DCR_FSIZE_SHIFT);
 }
 
+static void _stm32_qspi_set_cs(struct stm32_qspi_priv *priv, unsigned int cs)
+{
+	clrsetbits_le32(&priv->regs->cr, STM32_QSPI_CR_FSEL,
+			cs ? STM32_QSPI_CR_FSEL : 0);
+}
+
 static unsigned int _stm32_qspi_gen_ccr(struct stm32_qspi_priv *priv)
 {
 	unsigned int ccr_reg = 0;
@@ -504,10 +512,17 @@ static int stm32_qspi_claim_bus(struct udevice *dev)
 	struct stm32_qspi_priv *priv;
 	struct udevice *bus;
 	struct spi_flash *flash;
+	struct dm_spi_slave_platdata *slave_plat;
 
 	bus = dev->parent;
 	priv = dev_get_priv(bus);
 	flash = dev_get_uclass_priv(dev);
+	slave_plat = dev_get_parent_platdata(dev);
+
+	if (slave_plat->cs >= STM32_MAX_NORCHIP)
+		return -ENODEV;
+
+	_stm32_qspi_set_cs(priv, slave_plat->cs);
 
 	_stm32_qspi_set_flash_size(priv, flash->size);
 
-- 
1.9.1