linux/drivers/spi/spi-dw-mmio.c
Baruch Siach 020fe3fe11 spi: dw-mmio: prepare the clock before enabling
This is required for common clock support.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-31 12:30:22 +00:00

108 lines
2.4 KiB
C

/*
* Memory-mapped interface driver for DW SPI Core
*
* Copyright (c) 2010, Octasic semiconductor.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/scatterlist.h>
#include <linux/module.h>
#include "spi-dw.h"
#define DRIVER_NAME "dw_spi_mmio"
struct dw_spi_mmio {
struct dw_spi dws;
struct clk *clk;
};
static int dw_spi_mmio_probe(struct platform_device *pdev)
{
struct dw_spi_mmio *dwsmmio;
struct dw_spi *dws;
struct resource *mem;
int ret;
dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
GFP_KERNEL);
if (!dwsmmio)
return -ENOMEM;
dws = &dwsmmio->dws;
/* Get basic io resource and map it */
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(&pdev->dev, "no mem resource?\n");
return -EINVAL;
}
dws->regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(dws->regs)) {
dev_err(&pdev->dev, "SPI region map failed\n");
return PTR_ERR(dws->regs);
}
dws->irq = platform_get_irq(pdev, 0);
if (dws->irq < 0) {
dev_err(&pdev->dev, "no irq resource?\n");
return dws->irq; /* -ENXIO */
}
dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(dwsmmio->clk))
return PTR_ERR(dwsmmio->clk);
ret = clk_prepare_enable(dwsmmio->clk);
if (ret)
return ret;
dws->bus_num = 0;
dws->num_cs = 4;
dws->max_freq = clk_get_rate(dwsmmio->clk);
ret = dw_spi_add_host(&pdev->dev, dws);
if (ret)
goto out;
platform_set_drvdata(pdev, dwsmmio);
return 0;
out:
clk_disable_unprepare(dwsmmio->clk);
return ret;
}
static int dw_spi_mmio_remove(struct platform_device *pdev)
{
struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
clk_disable_unprepare(dwsmmio->clk);
dw_spi_remove_host(&dwsmmio->dws);
return 0;
}
static struct platform_driver dw_spi_mmio_driver = {
.probe = dw_spi_mmio_probe,
.remove = dw_spi_mmio_remove,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
},
};
module_platform_driver(dw_spi_mmio_driver);
MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
MODULE_LICENSE("GPL v2");