ramips: split mt7621 spi into a separate driver, increase maximum transfer size

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 43807

1 files changed, 343 insertions, 0 deletions

diff --git a/target/linux/ramips/patches-3.14/0061-SPI-ralink-add-mt7621-SoC-spi-driver.patch b/target/linux/ramips/patches-3.14/0061-SPI-ralink-add-mt7621-SoC-spi-driver.patch
new file mode 100644
index 0000000000..4b46603bf2
--- /dev/null
+++ b/target/linux/ramips/patches-3.14/0061-SPI-ralink-add-mt7621-SoC-spi-driver.patch
@@ -0,0 +1,343 @@
+--- a/drivers/spi/Kconfig
++++ b/drivers/spi/Kconfig
+@@ -396,6 +396,12 @@ config SPI_RT2880
+ 	help
+ 	  This selects a driver for the Ralink RT288x/RT305x SPI Controller.
+ 
++config SPI_MT7621
++	tristate "MediaTek MT7621 SPI Controller"
++	depends on RALINK
++	help
++	  This selects a driver for the MediaTek MT7621 SPI Controller.
++
+ config SPI_S3C24XX
+ 	tristate "Samsung S3C24XX series SPI"
+ 	depends on ARCH_S3C24XX
+--- a/drivers/spi/Makefile
++++ b/drivers/spi/Makefile
+@@ -44,6 +44,7 @@ obj-$(CONFIG_SPI_LM70_LLP)		+= spi-lm70l
+ obj-$(CONFIG_SPI_MPC512x_PSC)		+= spi-mpc512x-psc.o
+ obj-$(CONFIG_SPI_MPC52xx_PSC)		+= spi-mpc52xx-psc.o
+ obj-$(CONFIG_SPI_MPC52xx)		+= spi-mpc52xx.o
++obj-$(CONFIG_SPI_MT7621)		+= spi-mt7621.o
+ obj-$(CONFIG_SPI_MXS)			+= spi-mxs.o
+ obj-$(CONFIG_SPI_NUC900)		+= spi-nuc900.o
+ obj-$(CONFIG_SPI_OC_TINY)		+= spi-oc-tiny.o
+--- /dev/null
++++ b/drivers/spi/spi-mt7621.c
+@@ -0,0 +1,315 @@
++/*
++ * spi-mt7621.c -- MediaTek MT7621 SPI controller driver
++ *
++ * Copyright (C) 2011 Sergiy <piratfm@gmail.com>
++ * Copyright (C) 2011-2013 Gabor Juhos <juhosg@openwrt.org>
++ * Copyright (C) 2014-2015 Felix Fietkau <nbd@openwrt.org>
++ *
++ * Some parts are based on spi-orion.c:
++ *   Author: Shadi Ammouri <shadi@marvell.com>
++ *   Copyright (C) 2007-2008 Marvell Ltd.
++ *
++ * 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/module.h>
++#include <linux/clk.h>
++#include <linux/err.h>
++#include <linux/delay.h>
++#include <linux/io.h>
++#include <linux/reset.h>
++#include <linux/spi/spi.h>
++#include <linux/of_device.h>
++#include <linux/platform_device.h>
++#include <linux/swab.h>
++
++#include <ralink_regs.h>
++
++#define SPI_BPW_MASK(bits) BIT((bits) - 1)
++
++#define DRIVER_NAME			"spi-mt7621"
++/* in usec */
++#define RALINK_SPI_WAIT_MAX_LOOP	2000
++
++/* SPISTAT register bit field */
++#define SPISTAT_BUSY			BIT(0)
++
++#define MT7621_SPI_TRANS	0x00
++#define SPITRANS_BUSY		BIT(16)
++
++#define MT7621_SPI_OPCODE	0x04
++#define MT7621_SPI_DATA0	0x08
++#define SPI_CTL_TX_RX_CNT_MASK	0xff
++#define SPI_CTL_START		BIT(8)
++
++#define MT7621_SPI_POLAR	0x38
++#define MT7621_SPI_MASTER	0x28
++#define MT7621_SPI_MOREBUF	0x2c
++#define MT7621_SPI_SPACE	0x3c
++
++#define RT2880_SPI_MODE_BITS	(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH)
++
++struct mt7621_spi;
++
++struct mt7621_spi {
++	struct spi_master	*master;
++	void __iomem		*base;
++	unsigned int		sys_freq;
++	unsigned int		speed;
++	struct clk		*clk;
++	spinlock_t		lock;
++
++	struct mt7621_spi_ops	*ops;
++};
++
++static inline struct mt7621_spi *spidev_to_mt7621_spi(struct spi_device *spi)
++{
++	return spi_master_get_devdata(spi->master);
++}
++
++static inline u32 mt7621_spi_read(struct mt7621_spi *rs, u32 reg)
++{
++	return ioread32(rs->base + reg);
++}
++
++static inline void mt7621_spi_write(struct mt7621_spi *rs, u32 reg, u32 val)
++{
++	iowrite32(val, rs->base + reg);
++}
++
++static void mt7621_spi_set_cs(struct spi_device *spi, int enable)
++{
++	struct mt7621_spi *rs = spidev_to_mt7621_spi(spi);
++	u32 polar = mt7621_spi_read(rs, MT7621_SPI_POLAR);
++
++	if (enable)
++		polar |= 1;
++	else
++		polar &= ~1;
++	mt7621_spi_write(rs, MT7621_SPI_POLAR, polar);
++}
++
++static inline int mt7621_spi_wait_till_ready(struct spi_device *spi)
++{
++	struct mt7621_spi *rs = spidev_to_mt7621_spi(spi);
++	int i;
++
++	for (i = 0; i < RALINK_SPI_WAIT_MAX_LOOP; i++) {
++		u32 status;
++
++		status = mt7621_spi_read(rs, MT7621_SPI_TRANS);
++		if ((status & SPITRANS_BUSY) == 0) {
++			return 0;
++		}
++		cpu_relax();
++		udelay(1);
++	}
++
++	return -ETIMEDOUT;
++}
++
++static int mt7621_spi_transfer_one_message(struct spi_master *master,
++					   struct spi_message *m)
++{
++	struct mt7621_spi *rs = spi_master_get_devdata(master);
++	struct spi_device *spi = m->spi;
++	struct spi_transfer *t = NULL;
++	int status = 0;
++	int i, len = 0;
++	int rx_len = 0;
++	u32 data[9] = { 0 };
++	u32 val;
++
++	mt7621_spi_wait_till_ready(spi);
++
++	list_for_each_entry(t, &m->transfers, transfer_list) {
++		const u8 *buf = t->tx_buf;
++
++		if (t->rx_buf)
++			rx_len += t->len;
++
++		if (!buf)
++			continue;
++
++		if (WARN_ON(len + t->len > 36)) {
++			status = -EIO;
++			goto msg_done;
++		}
++
++		for (i = 0; i < t->len; i++, len++)
++			data[len / 4] |= buf[i] << (8 * (len & 3));
++	}
++
++	if (WARN_ON(rx_len > 32)) {
++		status = -EIO;
++		goto msg_done;
++	}
++
++	data[0] = swab32(data[0]);
++	if (len < 4)
++		data[0] >>= (4 - len) * 8;
++
++	for (i = 0; i < len; i += 4)
++		mt7621_spi_write(rs, MT7621_SPI_OPCODE + i, data[i / 4]);
++
++	val = (min_t(int, len, 4) * 8) << 24;
++	if (len > 4)
++		val |= (len - 4) * 8;
++	val |= (rx_len * 8) << 12;
++	mt7621_spi_write(rs, MT7621_SPI_MOREBUF, val);
++
++	mt7621_spi_set_cs(spi, 1);
++
++	val = mt7621_spi_read(rs, MT7621_SPI_TRANS);
++	val |= SPI_CTL_START;
++	mt7621_spi_write(rs, MT7621_SPI_TRANS, val);
++
++	mt7621_spi_wait_till_ready(spi);
++
++	mt7621_spi_set_cs(spi, 0);
++
++	for (i = 0; i < rx_len; i += 4)
++		data[i / 4] = mt7621_spi_read(rs, MT7621_SPI_DATA0 + i);
++
++	m->actual_length = len + rx_len;
++
++	len = 0;
++	list_for_each_entry(t, &m->transfers, transfer_list) {
++		u8 *buf = t->rx_buf;
++
++		if (!buf)
++			continue;
++
++		for (i = 0; i < t->len; i++, len++)
++			buf[i] = data[len / 4] >> (8 * (len & 3));
++	}
++
++msg_done:
++	m->status = status;
++	spi_finalize_current_message(master);
++
++	return 0;
++}
++
++static int mt7621_spi_setup(struct spi_device *spi)
++{
++	return 0;
++}
++
++static void mt7621_spi_reset(struct mt7621_spi *rs)
++{
++	u32 master = mt7621_spi_read(rs, MT7621_SPI_MASTER);
++
++	master &= ~(0xfff << 16);
++	master |= 13 << 16;
++	master |= 7 << 29;
++	master |= 1 << 2;
++
++	mt7621_spi_write(rs, MT7621_SPI_MASTER, master);
++}
++
++static const struct of_device_id mt7621_spi_match[] = {
++	{ .compatible = "ralink,mt7621-spi" },
++	{},
++};
++MODULE_DEVICE_TABLE(of, mt7621_spi_match);
++
++static int mt7621_spi_probe(struct platform_device *pdev)
++{
++	const struct of_device_id *match;
++	struct spi_master *master;
++	struct mt7621_spi *rs;
++	unsigned long flags;
++	void __iomem *base;
++	struct resource *r;
++	int status = 0;
++	struct clk *clk;
++	struct mt7621_spi_ops *ops;
++
++	match = of_match_device(mt7621_spi_match, &pdev->dev);
++	if (!match)
++		return -EINVAL;
++	ops = (struct mt7621_spi_ops *)match->data;
++
++	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++	base = devm_ioremap_resource(&pdev->dev, r);
++	if (IS_ERR(base))
++		return PTR_ERR(base);
++
++	clk = devm_clk_get(&pdev->dev, NULL);
++	if (IS_ERR(clk)) {
++		dev_err(&pdev->dev, "unable to get SYS clock, err=%d\n",
++			status);
++		return PTR_ERR(clk);
++	}
++
++	status = clk_prepare_enable(clk);
++	if (status)
++		return status;
++
++	master = spi_alloc_master(&pdev->dev, sizeof(*rs));
++	if (master == NULL) {
++		dev_dbg(&pdev->dev, "master allocation failed\n");
++		return -ENOMEM;
++	}
++
++	master->mode_bits = RT2880_SPI_MODE_BITS;
++
++	master->setup = mt7621_spi_setup;
++	master->transfer_one_message = mt7621_spi_transfer_one_message;
++	master->bits_per_word_mask = SPI_BPW_MASK(8);
++	master->dev.of_node = pdev->dev.of_node;
++	master->num_chipselect = 1;
++
++	dev_set_drvdata(&pdev->dev, master);
++
++	rs = spi_master_get_devdata(master);
++	rs->base = base;
++	rs->clk = clk;
++	rs->master = master;
++	rs->sys_freq = clk_get_rate(rs->clk);
++	rs->ops = ops;
++	dev_dbg(&pdev->dev, "sys_freq: %u\n", rs->sys_freq);
++	spin_lock_irqsave(&rs->lock, flags);
++
++	device_reset(&pdev->dev);
++
++	mt7621_spi_reset(rs);
++
++	return spi_register_master(master);
++}
++
++static int mt7621_spi_remove(struct platform_device *pdev)
++{
++	struct spi_master *master;
++	struct mt7621_spi *rs;
++
++	master = dev_get_drvdata(&pdev->dev);
++	rs = spi_master_get_devdata(master);
++
++	clk_disable(rs->clk);
++	spi_unregister_master(master);
++
++	return 0;
++}
++
++MODULE_ALIAS("platform:" DRIVER_NAME);
++
++static struct platform_driver mt7621_spi_driver = {
++	.driver = {
++		.name = DRIVER_NAME,
++		.owner = THIS_MODULE,
++		.of_match_table = mt7621_spi_match,
++	},
++	.probe = mt7621_spi_probe,
++	.remove = mt7621_spi_remove,
++};
++
++module_platform_driver(mt7621_spi_driver);
++
++MODULE_DESCRIPTION("MT7621 SPI driver");
++MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
++MODULE_LICENSE("GPL");