Merge remote-tracking branches 'spi/topic/xilinx' and 'spi/topic/xtfpga' into spi-next

This commit is contained in:
Mark Brown 2014-03-30 00:51:48 +00:00
commit 45b15d98a9
6 changed files with 205 additions and 20 deletions

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@ -0,0 +1,9 @@
Cadence Xtensa XTFPGA platform SPI controller.
This simple SPI master controller is built into xtfpga bitstreams and is used
to control daughterboard audio codec.
Required properties:
- compatible: should be "cdns,xtfpga-spi".
- reg: physical base address of the controller and length of memory mapped
region.

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@ -9782,6 +9782,12 @@ L: linux-serial@vger.kernel.org
S: Maintained
F: drivers/tty/serial/uartlite.c
XTENSA XTFPGA PLATFORM SUPPORT
M: Max Filippov <jcmvbkbc@gmail.com>
L: linux-xtensa@linux-xtensa.org
S: Maintained
F: drivers/spi/spi-xtensa-xtfpga.c
YAM DRIVER FOR AX.25
M: Jean-Paul Roubelat <jpr@f6fbb.org>
L: linux-hams@vger.kernel.org

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@ -538,6 +538,19 @@ config SPI_XILINX
Or for the DS570, see "XPS Serial Peripheral Interface (SPI) (v2.00b)"
config SPI_XTENSA_XTFPGA
tristate "Xtensa SPI controller for xtfpga"
depends on (XTENSA && XTENSA_PLATFORM_XTFPGA) || COMPILE_TEST
select SPI_BITBANG
help
SPI driver for xtfpga SPI master controller.
This simple SPI master controller is built into xtfpga bitstreams
and is used to control daughterboard audio codec. It always transfers
16 bit words in SPI mode 0, automatically asserting CS on transfer
start and deasserting on end.
config SPI_NUC900
tristate "Nuvoton NUC900 series SPI"
depends on ARCH_W90X900

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@ -81,3 +81,4 @@ obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o
obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o
obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
obj-$(CONFIG_SPI_XTENSA_XTFPGA) += spi-xtensa-xtfpga.o

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@ -87,10 +87,10 @@ struct xilinx_spi {
const u8 *tx_ptr; /* pointer in the Rx buffer */
int remaining_bytes; /* the number of bytes left to transfer */
u8 bits_per_word;
unsigned int (*read_fn) (void __iomem *);
void (*write_fn) (u32, void __iomem *);
void (*tx_fn) (struct xilinx_spi *);
void (*rx_fn) (struct xilinx_spi *);
unsigned int (*read_fn)(void __iomem *);
void (*write_fn)(u32, void __iomem *);
void (*tx_fn)(struct xilinx_spi *);
void (*rx_fn)(struct xilinx_spi *);
};
static void xspi_write32(u32 val, void __iomem *addr)
@ -208,26 +208,11 @@ static void xilinx_spi_chipselect(struct spi_device *spi, int is_on)
}
/* spi_bitbang requires custom setup_transfer() to be defined if there is a
* custom txrx_bufs(). We have nothing to setup here as the SPI IP block
* supports 8 or 16 bits per word which cannot be changed in software.
* SPI clock can't be changed in software either.
* Check for correct bits per word. Chip select delay calculations could be
* added here as soon as bitbang_work() can be made aware of the delay value.
* custom txrx_bufs().
*/
static int xilinx_spi_setup_transfer(struct spi_device *spi,
struct spi_transfer *t)
{
struct xilinx_spi *xspi = spi_master_get_devdata(spi->master);
u8 bits_per_word;
bits_per_word = (t && t->bits_per_word)
? t->bits_per_word : spi->bits_per_word;
if (bits_per_word != xspi->bits_per_word) {
dev_err(&spi->dev, "%s, unsupported bits_per_word=%d\n",
__func__, bits_per_word);
return -EINVAL;
}
return 0;
}
@ -406,6 +391,7 @@ static int xilinx_spi_probe(struct platform_device *pdev)
xspi->write_fn = xspi_write32_be;
}
master->bits_per_word_mask = SPI_BPW_MASK(bits_per_word);
xspi->bits_per_word = bits_per_word;
if (xspi->bits_per_word == 8) {
xspi->tx_fn = xspi_tx8;

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@ -0,0 +1,170 @@
/*
* Xtensa xtfpga SPI controller driver
*
* Copyright (c) 2014 Cadence Design Systems Inc.
*
* 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/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#define XTFPGA_SPI_NAME "xtfpga_spi"
#define XTFPGA_SPI_START 0x0
#define XTFPGA_SPI_BUSY 0x4
#define XTFPGA_SPI_DATA 0x8
#define BUSY_WAIT_US 100
struct xtfpga_spi {
struct spi_bitbang bitbang;
void __iomem *regs;
u32 data;
unsigned data_sz;
};
static inline void xtfpga_spi_write32(const struct xtfpga_spi *spi,
unsigned addr, u32 val)
{
iowrite32(val, spi->regs + addr);
}
static inline unsigned int xtfpga_spi_read32(const struct xtfpga_spi *spi,
unsigned addr)
{
return ioread32(spi->regs + addr);
}
static inline void xtfpga_spi_wait_busy(struct xtfpga_spi *xspi)
{
unsigned i;
for (i = 0; xtfpga_spi_read32(xspi, XTFPGA_SPI_BUSY) &&
i < BUSY_WAIT_US; ++i)
udelay(1);
WARN_ON_ONCE(i == BUSY_WAIT_US);
}
static u32 xtfpga_spi_txrx_word(struct spi_device *spi, unsigned nsecs,
u32 v, u8 bits)
{
struct xtfpga_spi *xspi = spi_master_get_devdata(spi->master);
xspi->data = (xspi->data << bits) | (v & GENMASK(bits - 1, 0));
xspi->data_sz += bits;
if (xspi->data_sz >= 16) {
xtfpga_spi_write32(xspi, XTFPGA_SPI_DATA,
xspi->data >> (xspi->data_sz - 16));
xspi->data_sz -= 16;
xtfpga_spi_write32(xspi, XTFPGA_SPI_START, 1);
xtfpga_spi_wait_busy(xspi);
xtfpga_spi_write32(xspi, XTFPGA_SPI_START, 0);
}
return 0;
}
static void xtfpga_spi_chipselect(struct spi_device *spi, int is_on)
{
struct xtfpga_spi *xspi = spi_master_get_devdata(spi->master);
WARN_ON(xspi->data_sz != 0);
xspi->data_sz = 0;
}
static int xtfpga_spi_probe(struct platform_device *pdev)
{
struct xtfpga_spi *xspi;
struct resource *mem;
int ret;
struct spi_master *master;
master = spi_alloc_master(&pdev->dev, sizeof(struct xtfpga_spi));
if (!master)
return -ENOMEM;
master->flags = SPI_MASTER_NO_RX;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
master->bus_num = pdev->dev.id;
master->dev.of_node = pdev->dev.of_node;
xspi = spi_master_get_devdata(master);
xspi->bitbang.master = master;
xspi->bitbang.chipselect = xtfpga_spi_chipselect;
xspi->bitbang.txrx_word[SPI_MODE_0] = xtfpga_spi_txrx_word;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(&pdev->dev, "No memory resource\n");
ret = -ENODEV;
goto err;
}
xspi->regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(xspi->regs)) {
ret = PTR_ERR(xspi->regs);
goto err;
}
xtfpga_spi_write32(xspi, XTFPGA_SPI_START, 0);
usleep_range(1000, 2000);
if (xtfpga_spi_read32(xspi, XTFPGA_SPI_BUSY)) {
dev_err(&pdev->dev, "Device stuck in busy state\n");
ret = -EBUSY;
goto err;
}
ret = spi_bitbang_start(&xspi->bitbang);
if (ret < 0) {
dev_err(&pdev->dev, "spi_bitbang_start failed\n");
goto err;
}
platform_set_drvdata(pdev, master);
return 0;
err:
spi_master_put(master);
return ret;
}
static int xtfpga_spi_remove(struct platform_device *pdev)
{
struct spi_master *master = platform_get_drvdata(pdev);
struct xtfpga_spi *xspi = spi_master_get_devdata(master);
spi_bitbang_stop(&xspi->bitbang);
spi_master_put(master);
return 0;
}
MODULE_ALIAS("platform:" XTFPGA_SPI_NAME);
#ifdef CONFIG_OF
static const struct of_device_id xtfpga_spi_of_match[] = {
{ .compatible = "cdns,xtfpga-spi", },
{}
};
MODULE_DEVICE_TABLE(of, xtfpga_spi_of_match);
#endif
static struct platform_driver xtfpga_spi_driver = {
.probe = xtfpga_spi_probe,
.remove = xtfpga_spi_remove,
.driver = {
.name = XTFPGA_SPI_NAME,
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(xtfpga_spi_of_match),
},
};
module_platform_driver(xtfpga_spi_driver);
MODULE_AUTHOR("Max Filippov <jcmvbkbc@gmail.com>");
MODULE_DESCRIPTION("xtensa xtfpga SPI driver");
MODULE_LICENSE("GPL");