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spi: altera: Switch to SPI core transfer queue management

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The Altera SPI driver currently uses the spi-bitbang infrastructure for
transfer queue management, but non of the bitbang functionality itself.
This is because when the driver was written this was the only way to not
have to do queue management in the driver itself.

Nowadays transfer queue management is available from the SPI driver core
itself and using the bitbang infrastructure just adds an additional level
of indirection.

Switch the driver over to using the core queue management directly.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Lars-Peter Clausen 2017-08-16 11:33:11 +02:00 committed by Mark Brown
parent 5771a8c088
commit e19b63cd3c
2 changed files with 27 additions and 68 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
drivers/spi/Kconfig
View file

@ -55,7 +55,6 @@ comment "SPI Master Controller Drivers"
config SPI_ALTERA config SPI_ALTERA
tristate "Altera SPI Controller" tristate "Altera SPI Controller"
select SPI_BITBANG
help help
This is the driver for the Altera SPI Controller. This is the driver for the Altera SPI Controller.

94
drivers/spi/spi-altera.c
View file

@ -18,7 +18,6 @@
#include <linux/module.h> #include <linux/module.h>
#include <linux/platform_device.h> #include <linux/platform_device.h>
#include <linux/spi/spi.h> #include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <linux/io.h> #include <linux/io.h>
#include <linux/of.h> #include <linux/of.h>
@ -45,10 +44,6 @@
#define ALTERA_SPI_CONTROL_SSO_MSK 0x400 #define ALTERA_SPI_CONTROL_SSO_MSK 0x400
struct altera_spi { struct altera_spi {
/* bitbang has to be first */
struct spi_bitbang bitbang;
struct completion done;
void __iomem *base; void __iomem *base;
int irq; int irq;
int len; int len;
@ -66,39 +61,18 @@ static inline struct altera_spi *altera_spi_to_hw(struct spi_device *sdev)
return spi_master_get_devdata(sdev->master); return spi_master_get_devdata(sdev->master);
} }
static void altera_spi_chipsel(struct spi_device *spi, int value) static void altera_spi_set_cs(struct spi_device *spi, bool is_high)
{ {
struct altera_spi *hw = altera_spi_to_hw(spi); struct altera_spi *hw = altera_spi_to_hw(spi);
if (spi->mode & SPI_CS_HIGH) { if (is_high) {
switch (value) { hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK;
case BITBANG_CS_INACTIVE: writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
writel(1 << spi->chip_select, writel(0, hw->base + ALTERA_SPI_SLAVE_SEL);
hw->base + ALTERA_SPI_SLAVE_SEL);
hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK;
writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
break;
case BITBANG_CS_ACTIVE:
hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK;
writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
writel(0, hw->base + ALTERA_SPI_SLAVE_SEL);
break;
}
} else { } else {
switch (value) { writel(BIT(spi->chip_select), hw->base + ALTERA_SPI_SLAVE_SEL);
case BITBANG_CS_INACTIVE: hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK;
hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK; writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
break;
case BITBANG_CS_ACTIVE:
writel(1 << spi->chip_select,
hw->base + ALTERA_SPI_SLAVE_SEL);
hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK;
writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
break;
}
} }
} }
@ -116,9 +90,10 @@ static inline unsigned int hw_txbyte(struct altera_spi *hw, int count)
return 0; return 0;
} }
static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t) static int altera_spi_txrx(struct spi_master *master,
struct spi_device *spi, struct spi_transfer *t)
{ {
struct altera_spi *hw = altera_spi_to_hw(spi); struct altera_spi *hw = spi_master_get_devdata(master);
hw->tx = t->tx_buf; hw->tx = t->tx_buf;
hw->rx = t->rx_buf; hw->rx = t->rx_buf;
@ -133,11 +108,6 @@ static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
/* send the first byte */ /* send the first byte */
writel(hw_txbyte(hw, 0), hw->base + ALTERA_SPI_TXDATA); writel(hw_txbyte(hw, 0), hw->base + ALTERA_SPI_TXDATA);
wait_for_completion(&hw->done);
/* disable receive interrupt */
hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK;
writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
} else { } else {
while (hw->count < hw->len) { while (hw->count < hw->len) {
unsigned int rxd; unsigned int rxd;
@ -164,14 +134,16 @@ static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
hw->count++; hw->count++;
} }
spi_finalize_current_transfer(master);
} }
return hw->count * hw->bytes_per_word; return t->len;
} }
static irqreturn_t altera_spi_irq(int irq, void *dev) static irqreturn_t altera_spi_irq(int irq, void *dev)
{ {
struct altera_spi *hw = dev; struct spi_master *master = dev;
struct altera_spi *hw = spi_master_get_devdata(master);
unsigned int rxd; unsigned int rxd;
rxd = readl(hw->base + ALTERA_SPI_RXDATA); rxd = readl(hw->base + ALTERA_SPI_RXDATA);
@ -189,10 +161,15 @@ static irqreturn_t altera_spi_irq(int irq, void *dev)
hw->count++; hw->count++;
if (hw->count < hw->len) if (hw->count < hw->len) {
writel(hw_txbyte(hw, hw->count), hw->base + ALTERA_SPI_TXDATA); writel(hw_txbyte(hw, hw->count), hw->base + ALTERA_SPI_TXDATA);
else } else {
complete(&hw->done); /* disable receive interrupt */
hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK;
writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
spi_finalize_current_transfer(master);
}
return IRQ_HANDLED; return IRQ_HANDLED;
} }
@ -214,14 +191,10 @@ static int altera_spi_probe(struct platform_device *pdev)
master->mode_bits = SPI_CS_HIGH; master->mode_bits = SPI_CS_HIGH;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16); master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
master->dev.of_node = pdev->dev.of_node; master->dev.of_node = pdev->dev.of_node;
master->transfer_one = altera_spi_txrx;
master->set_cs = altera_spi_set_cs;
hw = spi_master_get_devdata(master); hw = spi_master_get_devdata(master);
platform_set_drvdata(pdev, hw);
/* setup the state for the bitbang driver */
hw->bitbang.master = master;
hw->bitbang.chipselect = altera_spi_chipsel;
hw->bitbang.txrx_bufs = altera_spi_txrx;
/* find and map our resources */ /* find and map our resources */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0); res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@ -239,15 +212,13 @@ static int altera_spi_probe(struct platform_device *pdev)
/* irq is optional */ /* irq is optional */
hw->irq = platform_get_irq(pdev, 0); hw->irq = platform_get_irq(pdev, 0);
if (hw->irq >= 0) { if (hw->irq >= 0) {
init_completion(&hw->done);
err = devm_request_irq(&pdev->dev, hw->irq, altera_spi_irq, 0, err = devm_request_irq(&pdev->dev, hw->irq, altera_spi_irq, 0,
pdev->name, hw); pdev->name, master);
if (err) if (err)
goto exit; goto exit;
} }
/* register our spi controller */ err = devm_spi_register_master(&pdev->dev, master);
err = spi_bitbang_start(&hw->bitbang);
if (err) if (err)
goto exit; goto exit;
dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq); dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq);
@ -258,16 +229,6 @@ static int altera_spi_probe(struct platform_device *pdev)
return err; return err;
} }
static int altera_spi_remove(struct platform_device *dev)
{
struct altera_spi *hw = platform_get_drvdata(dev);
struct spi_master *master = hw->bitbang.master;
spi_bitbang_stop(&hw->bitbang);
spi_master_put(master);
return 0;
}
#ifdef CONFIG_OF #ifdef CONFIG_OF
static const struct of_device_id altera_spi_match[] = { static const struct of_device_id altera_spi_match[] = {
{ .compatible = "ALTR,spi-1.0", }, { .compatible = "ALTR,spi-1.0", },
@ -279,7 +240,6 @@ MODULE_DEVICE_TABLE(of, altera_spi_match);
static struct platform_driver altera_spi_driver = { static struct platform_driver altera_spi_driver = {
.probe = altera_spi_probe, .probe = altera_spi_probe,
.remove = altera_spi_remove,
.driver = { .driver = {
.name = DRV_NAME, .name = DRV_NAME,
.pm = NULL, .pm = NULL,