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path: root/drivers/spi/spi-altera.c
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Diffstat (limited to 'drivers/spi/spi-altera.c')
-rw-r--r--drivers/spi/spi-altera.c179
1 files changed, 155 insertions, 24 deletions
diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c
index 41d71ba7fd32..809bfff3690a 100644
--- a/drivers/spi/spi-altera.c
+++ b/drivers/spi/spi-altera.c
@@ -14,6 +14,7 @@
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/spi/altera.h>
#include <linux/spi/spi.h>
#include <linux/io.h>
#include <linux/of.h>
@@ -40,19 +41,61 @@
#define ALTERA_SPI_CONTROL_IE_MSK 0x100
#define ALTERA_SPI_CONTROL_SSO_MSK 0x400
+#define ALTERA_SPI_MAX_CS 32
+
+enum altera_spi_type {
+ ALTERA_SPI_TYPE_UNKNOWN,
+ ALTERA_SPI_TYPE_SUBDEV,
+};
+
struct altera_spi {
- void __iomem *base;
int irq;
int len;
int count;
int bytes_per_word;
- unsigned long imr;
+ u32 imr;
/* data buffers */
const unsigned char *tx;
unsigned char *rx;
+
+ struct regmap *regmap;
+ u32 regoff;
+ struct device *dev;
+};
+
+static const struct regmap_config spi_altera_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .fast_io = true,
};
+static int altr_spi_writel(struct altera_spi *hw, unsigned int reg,
+ unsigned int val)
+{
+ int ret;
+
+ ret = regmap_write(hw->regmap, hw->regoff + reg, val);
+ if (ret)
+ dev_err(hw->dev, "fail to write reg 0x%x val 0x%x: %d\n",
+ reg, val, ret);
+
+ return ret;
+}
+
+static int altr_spi_readl(struct altera_spi *hw, unsigned int reg,
+ unsigned int *val)
+{
+ int ret;
+
+ ret = regmap_read(hw->regmap, hw->regoff + reg, val);
+ if (ret)
+ dev_err(hw->dev, "fail to read reg 0x%x: %d\n", reg, ret);
+
+ return ret;
+}
+
static inline struct altera_spi *altera_spi_to_hw(struct spi_device *sdev)
{
return spi_master_get_devdata(sdev->master);
@@ -64,12 +107,13 @@ static void altera_spi_set_cs(struct spi_device *spi, bool is_high)
if (is_high) {
hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK;
- writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
- writel(0, hw->base + ALTERA_SPI_SLAVE_SEL);
+ altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr);
+ altr_spi_writel(hw, ALTERA_SPI_SLAVE_SEL, 0);
} else {
- writel(BIT(spi->chip_select), hw->base + ALTERA_SPI_SLAVE_SEL);
+ altr_spi_writel(hw, ALTERA_SPI_SLAVE_SEL,
+ BIT(spi->chip_select));
hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK;
- writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+ altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr);
}
}
@@ -86,17 +130,24 @@ static void altera_spi_tx_word(struct altera_spi *hw)
txd = (hw->tx[hw->count * 2]
| (hw->tx[hw->count * 2 + 1] << 8));
break;
+ case 4:
+ txd = (hw->tx[hw->count * 4]
+ | (hw->tx[hw->count * 4 + 1] << 8)
+ | (hw->tx[hw->count * 4 + 2] << 16)
+ | (hw->tx[hw->count * 4 + 3] << 24));
+ break;
+
}
}
- writel(txd, hw->base + ALTERA_SPI_TXDATA);
+ altr_spi_writel(hw, ALTERA_SPI_TXDATA, txd);
}
static void altera_spi_rx_word(struct altera_spi *hw)
{
unsigned int rxd;
- rxd = readl(hw->base + ALTERA_SPI_RXDATA);
+ altr_spi_readl(hw, ALTERA_SPI_RXDATA, &rxd);
if (hw->rx) {
switch (hw->bytes_per_word) {
case 1:
@@ -106,6 +157,13 @@ static void altera_spi_rx_word(struct altera_spi *hw)
hw->rx[hw->count * 2] = rxd;
hw->rx[hw->count * 2 + 1] = rxd >> 8;
break;
+ case 4:
+ hw->rx[hw->count * 4] = rxd;
+ hw->rx[hw->count * 4 + 1] = rxd >> 8;
+ hw->rx[hw->count * 4 + 2] = rxd >> 16;
+ hw->rx[hw->count * 4 + 3] = rxd >> 24;
+ break;
+
}
}
@@ -116,6 +174,7 @@ static int altera_spi_txrx(struct spi_master *master,
struct spi_device *spi, struct spi_transfer *t)
{
struct altera_spi *hw = spi_master_get_devdata(master);
+ u32 val;
hw->tx = t->tx_buf;
hw->rx = t->rx_buf;
@@ -126,7 +185,7 @@ static int altera_spi_txrx(struct spi_master *master,
if (hw->irq >= 0) {
/* enable receive interrupt */
hw->imr |= ALTERA_SPI_CONTROL_IRRDY_MSK;
- writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+ altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr);
/* send the first byte */
altera_spi_tx_word(hw);
@@ -134,9 +193,13 @@ static int altera_spi_txrx(struct spi_master *master,
while (hw->count < hw->len) {
altera_spi_tx_word(hw);
- while (!(readl(hw->base + ALTERA_SPI_STATUS) &
- ALTERA_SPI_STATUS_RRDY_MSK))
+ for (;;) {
+ altr_spi_readl(hw, ALTERA_SPI_STATUS, &val);
+ if (val & ALTERA_SPI_STATUS_RRDY_MSK)
+ break;
+
cpu_relax();
+ }
altera_spi_rx_word(hw);
}
@@ -158,7 +221,7 @@ static irqreturn_t altera_spi_irq(int irq, void *dev)
} else {
/* disable receive interrupt */
hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK;
- writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+ altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr);
spi_finalize_current_transfer(master);
}
@@ -168,9 +231,14 @@ static irqreturn_t altera_spi_irq(int irq, void *dev)
static int altera_spi_probe(struct platform_device *pdev)
{
+ const struct platform_device_id *platid = platform_get_device_id(pdev);
+ struct altera_spi_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ enum altera_spi_type type = ALTERA_SPI_TYPE_UNKNOWN;
struct altera_spi *hw;
struct spi_master *master;
int err = -ENODEV;
+ u32 val;
+ u16 i;
master = spi_alloc_master(&pdev->dev, sizeof(struct altera_spi));
if (!master)
@@ -178,27 +246,72 @@ static int altera_spi_probe(struct platform_device *pdev)
/* setup the master state. */
master->bus_num = pdev->id;
- master->num_chipselect = 16;
- master->mode_bits = SPI_CS_HIGH;
- master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
+
+ if (pdata) {
+ if (pdata->num_chipselect > ALTERA_SPI_MAX_CS) {
+ dev_err(&pdev->dev,
+ "Invalid number of chipselect: %hu\n",
+ pdata->num_chipselect);
+ return -EINVAL;
+ }
+
+ master->num_chipselect = pdata->num_chipselect;
+ master->mode_bits = pdata->mode_bits;
+ master->bits_per_word_mask = pdata->bits_per_word_mask;
+ } else {
+ master->num_chipselect = 16;
+ master->mode_bits = SPI_CS_HIGH;
+ master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
+ }
+
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->dev = &pdev->dev;
+
+ if (platid)
+ type = platid->driver_data;
/* find and map our resources */
- hw->base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(hw->base)) {
- err = PTR_ERR(hw->base);
- goto exit;
+ if (type == ALTERA_SPI_TYPE_SUBDEV) {
+ struct resource *regoff;
+
+ hw->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!hw->regmap) {
+ dev_err(&pdev->dev, "get regmap failed\n");
+ goto exit;
+ }
+
+ regoff = platform_get_resource(pdev, IORESOURCE_REG, 0);
+ if (regoff)
+ hw->regoff = regoff->start;
+ } else {
+ void __iomem *res;
+
+ res = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(res)) {
+ err = PTR_ERR(res);
+ goto exit;
+ }
+
+ hw->regmap = devm_regmap_init_mmio(&pdev->dev, res,
+ &spi_altera_config);
+ if (IS_ERR(hw->regmap)) {
+ dev_err(&pdev->dev, "regmap mmio init failed\n");
+ err = PTR_ERR(hw->regmap);
+ goto exit;
+ }
}
+
/* program defaults into the registers */
hw->imr = 0; /* disable spi interrupts */
- writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
- writel(0, hw->base + ALTERA_SPI_STATUS); /* clear status reg */
- if (readl(hw->base + ALTERA_SPI_STATUS) & ALTERA_SPI_STATUS_RRDY_MSK)
- readl(hw->base + ALTERA_SPI_RXDATA); /* flush rxdata */
+ altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr);
+ altr_spi_writel(hw, ALTERA_SPI_STATUS, 0); /* clear status reg */
+ altr_spi_readl(hw, ALTERA_SPI_STATUS, &val);
+ if (val & ALTERA_SPI_STATUS_RRDY_MSK)
+ altr_spi_readl(hw, ALTERA_SPI_RXDATA, &val); /* flush rxdata */
/* irq is optional */
hw->irq = platform_get_irq(pdev, 0);
if (hw->irq >= 0) {
@@ -211,7 +324,17 @@ static int altera_spi_probe(struct platform_device *pdev)
err = devm_spi_register_master(&pdev->dev, master);
if (err)
goto exit;
- dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq);
+
+ if (pdata) {
+ for (i = 0; i < pdata->num_devices; i++) {
+ if (!spi_new_device(master, pdata->devices + i))
+ dev_warn(&pdev->dev,
+ "unable to create SPI device: %s\n",
+ pdata->devices[i].modalias);
+ }
+ }
+
+ dev_info(&pdev->dev, "regoff %u, irq %d\n", hw->regoff, hw->irq);
return 0;
exit:
@@ -228,6 +351,13 @@ static const struct of_device_id altera_spi_match[] = {
MODULE_DEVICE_TABLE(of, altera_spi_match);
#endif /* CONFIG_OF */
+static const struct platform_device_id altera_spi_ids[] = {
+ { DRV_NAME, ALTERA_SPI_TYPE_UNKNOWN },
+ { "subdev_spi_altera", ALTERA_SPI_TYPE_SUBDEV },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, altera_spi_ids);
+
static struct platform_driver altera_spi_driver = {
.probe = altera_spi_probe,
.driver = {
@@ -235,6 +365,7 @@ static struct platform_driver altera_spi_driver = {
.pm = NULL,
.of_match_table = of_match_ptr(altera_spi_match),
},
+ .id_table = altera_spi_ids,
};
module_platform_driver(altera_spi_driver);
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-15 18:22:35 +0300