summaryrefslogtreecommitdiff
path: root/drivers/spi/spi-oc-tiny.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi-oc-tiny.c')
-rw-r--r--drivers/spi/spi-oc-tiny.c192
1 files changed, 42 insertions, 150 deletions
diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c
index 58deb79d046b..cba229920357 100644
--- a/drivers/spi/spi-oc-tiny.c
+++ b/drivers/spi/spi-oc-tiny.c
@@ -1,7 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
- * OpenCores tiny SPI master driver
+ * OpenCores tiny SPI host driver
*
- * http://opencores.org/project,tiny_spi
+ * https://opencores.org/project,tiny_spi
*
* Copyright (C) 2011 Thomas Chou <thomas@wytron.com.tw>
*
@@ -9,13 +10,8 @@
* Copyright (c) 2006 Ben Dooks
* Copyright (c) 2006 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
*/
-#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/module.h>
@@ -24,7 +20,6 @@
#include <linux/spi/spi_bitbang.h>
#include <linux/spi/spi_oc_tiny.h>
#include <linux/io.h>
-#include <linux/gpio.h>
#include <linux/of.h>
#define DRV_NAME "spi_oc_tiny"
@@ -54,13 +49,11 @@ struct tiny_spi {
unsigned int txc, rxc;
const u8 *txp;
u8 *rxp;
- int gpio_cs_count;
- int *gpio_cs;
};
static inline struct tiny_spi *tiny_spi_to_hw(struct spi_device *sdev)
{
- return spi_master_get_devdata(sdev->master);
+ return spi_controller_get_devdata(sdev->controller);
}
static unsigned int tiny_spi_baud(struct spi_device *spi, unsigned int hz)
@@ -70,16 +63,6 @@ static unsigned int tiny_spi_baud(struct spi_device *spi, unsigned int hz)
return min(DIV_ROUND_UP(hw->freq, hz * 2), (1U << hw->baudwidth)) - 1;
}
-static void tiny_spi_chipselect(struct spi_device *spi, int is_active)
-{
- struct tiny_spi *hw = tiny_spi_to_hw(spi);
-
- if (hw->gpio_cs_count > 0) {
- gpio_set_value(hw->gpio_cs[spi->chip_select],
- (spi->mode & SPI_CS_HIGH) ? is_active : !is_active);
- }
-}
-
static int tiny_spi_setup_transfer(struct spi_device *spi,
struct spi_transfer *t)
{
@@ -103,7 +86,7 @@ static int tiny_spi_setup(struct spi_device *spi)
hw->speed_hz = spi->max_speed_hz;
hw->baud = tiny_spi_baud(spi, hw->speed_hz);
}
- hw->mode = spi->mode & (SPI_CPOL | SPI_CPHA);
+ hw->mode = spi->mode & SPI_MODE_X_MASK;
return 0;
}
@@ -153,62 +136,22 @@ static int tiny_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
}
wait_for_completion(&hw->done);
- } else if (txp && rxp) {
- /* we need to tighten the transfer loop */
- writeb(*txp++, hw->base + TINY_SPI_TXDATA);
- if (t->len > 1) {
- writeb(*txp++, hw->base + TINY_SPI_TXDATA);
- for (i = 2; i < t->len; i++) {
- u8 rx, tx = *txp++;
- tiny_spi_wait_txr(hw);
- rx = readb(hw->base + TINY_SPI_TXDATA);
- writeb(tx, hw->base + TINY_SPI_TXDATA);
- *rxp++ = rx;
- }
- tiny_spi_wait_txr(hw);
- *rxp++ = readb(hw->base + TINY_SPI_TXDATA);
- }
- tiny_spi_wait_txe(hw);
- *rxp++ = readb(hw->base + TINY_SPI_RXDATA);
- } else if (rxp) {
- writeb(0, hw->base + TINY_SPI_TXDATA);
- if (t->len > 1) {
- writeb(0,
- hw->base + TINY_SPI_TXDATA);
- for (i = 2; i < t->len; i++) {
- u8 rx;
- tiny_spi_wait_txr(hw);
- rx = readb(hw->base + TINY_SPI_TXDATA);
- writeb(0, hw->base + TINY_SPI_TXDATA);
- *rxp++ = rx;
- }
- tiny_spi_wait_txr(hw);
- *rxp++ = readb(hw->base + TINY_SPI_TXDATA);
- }
- tiny_spi_wait_txe(hw);
- *rxp++ = readb(hw->base + TINY_SPI_RXDATA);
- } else if (txp) {
- writeb(*txp++, hw->base + TINY_SPI_TXDATA);
- if (t->len > 1) {
- writeb(*txp++, hw->base + TINY_SPI_TXDATA);
- for (i = 2; i < t->len; i++) {
- u8 tx = *txp++;
- tiny_spi_wait_txr(hw);
- writeb(tx, hw->base + TINY_SPI_TXDATA);
- }
- }
- tiny_spi_wait_txe(hw);
} else {
- writeb(0, hw->base + TINY_SPI_TXDATA);
- if (t->len > 1) {
- writeb(0, hw->base + TINY_SPI_TXDATA);
- for (i = 2; i < t->len; i++) {
+ /* we need to tighten the transfer loop */
+ writeb(txp ? *txp++ : 0, hw->base + TINY_SPI_TXDATA);
+ for (i = 1; i < t->len; i++) {
+ writeb(txp ? *txp++ : 0, hw->base + TINY_SPI_TXDATA);
+
+ if (rxp || (i != t->len - 1))
tiny_spi_wait_txr(hw);
- writeb(0, hw->base + TINY_SPI_TXDATA);
- }
+ if (rxp)
+ *rxp++ = readb(hw->base + TINY_SPI_TXDATA);
}
tiny_spi_wait_txe(hw);
+ if (rxp)
+ *rxp++ = readb(hw->base + TINY_SPI_RXDATA);
}
+
return t->len;
}
@@ -241,39 +184,19 @@ static irqreturn_t tiny_spi_irq(int irq, void *dev)
}
#ifdef CONFIG_OF
-#include <linux/of_gpio.h>
-
static int tiny_spi_of_probe(struct platform_device *pdev)
{
struct tiny_spi *hw = platform_get_drvdata(pdev);
struct device_node *np = pdev->dev.of_node;
- unsigned int i;
- const __be32 *val;
- int len;
+ u32 val;
if (!np)
return 0;
- hw->gpio_cs_count = of_gpio_count(np);
- if (hw->gpio_cs_count > 0) {
- hw->gpio_cs = devm_kzalloc(&pdev->dev,
- hw->gpio_cs_count * sizeof(unsigned int),
- GFP_KERNEL);
- if (!hw->gpio_cs)
- return -ENOMEM;
- }
- for (i = 0; i < hw->gpio_cs_count; i++) {
- hw->gpio_cs[i] = of_get_gpio_flags(np, i, NULL);
- if (hw->gpio_cs[i] < 0)
- return -ENODEV;
- }
- hw->bitbang.master->dev.of_node = pdev->dev.of_node;
- val = of_get_property(pdev->dev.of_node,
- "clock-frequency", &len);
- if (val && len >= sizeof(__be32))
- hw->freq = be32_to_cpup(val);
- val = of_get_property(pdev->dev.of_node, "baud-width", &len);
- if (val && len >= sizeof(__be32))
- hw->baudwidth = be32_to_cpup(val);
+ hw->bitbang.ctlr->dev.of_node = pdev->dev.of_node;
+ if (!of_property_read_u32(np, "clock-frequency", &val))
+ hw->freq = val;
+ if (!of_property_read_u32(np, "baud-width", &val))
+ hw->baudwidth = val;
return 0;
}
#else /* !CONFIG_OF */
@@ -285,45 +208,35 @@ static int tiny_spi_of_probe(struct platform_device *pdev)
static int tiny_spi_probe(struct platform_device *pdev)
{
- struct tiny_spi_platform_data *platp = pdev->dev.platform_data;
+ struct tiny_spi_platform_data *platp = dev_get_platdata(&pdev->dev);
struct tiny_spi *hw;
- struct spi_master *master;
- struct resource *res;
- unsigned int i;
+ struct spi_controller *host;
int err = -ENODEV;
- master = spi_alloc_master(&pdev->dev, sizeof(struct tiny_spi));
- if (!master)
+ host = spi_alloc_host(&pdev->dev, sizeof(struct tiny_spi));
+ if (!host)
return err;
- /* setup the master state. */
- master->bus_num = pdev->id;
- master->num_chipselect = 255;
- master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
- master->setup = tiny_spi_setup;
+ /* setup the host state. */
+ host->bus_num = pdev->id;
+ host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+ host->setup = tiny_spi_setup;
+ host->use_gpio_descriptors = true;
- hw = spi_master_get_devdata(master);
+ hw = spi_controller_get_devdata(host);
platform_set_drvdata(pdev, hw);
/* setup the state for the bitbang driver */
- hw->bitbang.master = spi_master_get(master);
- if (!hw->bitbang.master)
- return err;
+ hw->bitbang.ctlr = host;
hw->bitbang.setup_transfer = tiny_spi_setup_transfer;
- hw->bitbang.chipselect = tiny_spi_chipselect;
hw->bitbang.txrx_bufs = tiny_spi_txrx_bufs;
/* find and map our resources */
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- goto exit_busy;
- if (!devm_request_mem_region(&pdev->dev, res->start, resource_size(res),
- pdev->name))
- goto exit_busy;
- hw->base = devm_ioremap_nocache(&pdev->dev, res->start,
- resource_size(res));
- if (!hw->base)
- goto exit_busy;
+ hw->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(hw->base)) {
+ err = PTR_ERR(hw->base);
+ goto exit;
+ }
/* irq is optional */
hw->irq = platform_get_irq(pdev, 0);
if (hw->irq >= 0) {
@@ -335,10 +248,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
}
/* find platform data */
if (platp) {
- hw->gpio_cs_count = platp->gpio_cs_count;
- hw->gpio_cs = platp->gpio_cs;
- if (platp->gpio_cs_count && !platp->gpio_cs)
- goto exit_busy;
hw->freq = platp->freq;
hw->baudwidth = platp->baudwidth;
} else {
@@ -346,13 +255,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
if (err)
goto exit;
}
- for (i = 0; i < hw->gpio_cs_count; i++) {
- err = gpio_request(hw->gpio_cs[i], dev_name(&pdev->dev));
- if (err)
- goto exit_gpio;
- gpio_direction_output(hw->gpio_cs[i], 1);
- }
- hw->bitbang.master->num_chipselect = max(1, hw->gpio_cs_count);
/* register our spi controller */
err = spi_bitbang_start(&hw->bitbang);
@@ -362,27 +264,18 @@ static int tiny_spi_probe(struct platform_device *pdev)
return 0;
-exit_gpio:
- while (i-- > 0)
- gpio_free(hw->gpio_cs[i]);
-exit_busy:
- err = -EBUSY;
exit:
- spi_master_put(master);
+ spi_controller_put(host);
return err;
}
-static int tiny_spi_remove(struct platform_device *pdev)
+static void tiny_spi_remove(struct platform_device *pdev)
{
struct tiny_spi *hw = platform_get_drvdata(pdev);
- struct spi_master *master = hw->bitbang.master;
- unsigned int i;
+ struct spi_controller *host = hw->bitbang.ctlr;
spi_bitbang_stop(&hw->bitbang);
- for (i = 0; i < hw->gpio_cs_count; i++)
- gpio_free(hw->gpio_cs[i]);
- spi_master_put(master);
- return 0;
+ spi_controller_put(host);
}
#ifdef CONFIG_OF
@@ -398,7 +291,6 @@ static struct platform_driver tiny_spi_driver = {
.remove = tiny_spi_remove,
.driver = {
.name = DRV_NAME,
- .owner = THIS_MODULE,
.pm = NULL,
.of_match_table = of_match_ptr(tiny_spi_match),
},