lkml.org 
[lkml]   [2020]   [Jan]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 6/6] spi: rspi: Add support for GPIO chip selects
Date
Add support for GPIO chip selects using GPIO descriptors.  As the RSPI
controller always drives a native chip select when performing a
transfer, at least one native chip select must be left unused.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/spi/spi-rspi.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 2f5a856a93192702..85575d45901cee1b 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -242,6 +242,7 @@ struct spi_ops {
u16 mode_bits;
u16 flags;
u16 fifo_size;
+ u8 num_hw_ss;
};

/*
@@ -934,7 +935,8 @@ static int rspi_prepare_message(struct spi_controller *ctlr,
rspi->spcmd |= SPCMD_CPHA;

/* Configure slave signal to assert */
- rspi->spcmd |= SPCMD_SSLA(spi->chip_select);
+ rspi->spcmd |= SPCMD_SSLA(spi->cs_gpiod ? rspi->ctlr->unused_native_cs
+ : spi->chip_select);

/* CMOS output mode and MOSI signal from previous transfer */
rspi->sppcr = 0;
@@ -1123,6 +1125,7 @@ static const struct spi_ops rspi_ops = {
.mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP,
.flags = SPI_CONTROLLER_MUST_TX,
.fifo_size = 8,
+ .num_hw_ss = 2,
};

static const struct spi_ops rspi_rz_ops = {
@@ -1131,6 +1134,7 @@ static const struct spi_ops rspi_rz_ops = {
.mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP,
.flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
.fifo_size = 8, /* 8 for TX, 32 for RX */
+ .num_hw_ss = 1,
};

static const struct spi_ops qspi_ops = {
@@ -1141,6 +1145,7 @@ static const struct spi_ops qspi_ops = {
SPI_RX_DUAL | SPI_RX_QUAD,
.flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
.fifo_size = 32,
+ .num_hw_ss = 1,
};

#ifdef CONFIG_OF
@@ -1256,6 +1261,8 @@ static int rspi_probe(struct platform_device *pdev)
ctlr->mode_bits = ops->mode_bits;
ctlr->flags = ops->flags;
ctlr->dev.of_node = pdev->dev.of_node;
+ ctlr->use_gpio_descriptors = true;
+ ctlr->max_native_cs = rspi->ops->num_hw_ss;

ret = platform_get_irq_byname_optional(pdev, "rx");
if (ret < 0) {
--
2.17.1
\
 
 \ /
  Last update: 2020-01-02 15:05    [W:0.068 / U:36.808 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site