linux/drivers/mfd/mcp-sa11x0.c

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/*
* linux/drivers/mfd/mcp-sa11x0.c
*
* Copyright (C) 2001-2005 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*
* SA11x0 MCP (Multimedia Communications Port) driver.
*
* MCP read/write timeouts from Jordi Colomer, rehacked by rmk.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/mfd/mcp.h>
#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <asm/system.h>
#include <mach/mcp.h>
#include <mach/assabet.h>
#define DRIVER_NAME "sa11x0-mcp"
struct mcp_sa11x0 {
u32 mccr0;
u32 mccr1;
};
#define priv(mcp) ((struct mcp_sa11x0 *)mcp_priv(mcp))
static void
mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
{
unsigned int mccr0;
divisor /= 32;
mccr0 = Ser4MCCR0 & ~0x00007f00;
mccr0 |= divisor << 8;
Ser4MCCR0 = mccr0;
}
static void
mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
{
unsigned int mccr0;
divisor /= 32;
mccr0 = Ser4MCCR0 & ~0x0000007f;
mccr0 |= divisor;
Ser4MCCR0 = mccr0;
}
/*
* Write data to the device. The bit should be set after 3 subframe
* times (each frame is 64 clocks). We wait a maximum of 6 subframes.
* We really should try doing something more productive while we
* wait.
*/
static void
mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
{
int ret = -ETIME;
int i;
Ser4MCDR2 = reg << 17 | MCDR2_Wr | (val & 0xffff);
for (i = 0; i < 2; i++) {
udelay(mcp->rw_timeout);
if (Ser4MCSR & MCSR_CWC) {
ret = 0;
break;
}
}
if (ret < 0)
printk(KERN_WARNING "mcp: write timed out\n");
}
/*
* Read data from the device. The bit should be set after 3 subframe
* times (each frame is 64 clocks). We wait a maximum of 6 subframes.
* We really should try doing something more productive while we
* wait.
*/
static unsigned int
mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
{
int ret = -ETIME;
int i;
Ser4MCDR2 = reg << 17 | MCDR2_Rd;
for (i = 0; i < 2; i++) {
udelay(mcp->rw_timeout);
if (Ser4MCSR & MCSR_CRC) {
ret = Ser4MCDR2 & 0xffff;
break;
}
}
if (ret < 0)
printk(KERN_WARNING "mcp: read timed out\n");
return ret;
}
static void mcp_sa11x0_enable(struct mcp *mcp)
{
Ser4MCSR = -1;
Ser4MCCR0 |= MCCR0_MCE;
}
static void mcp_sa11x0_disable(struct mcp *mcp)
{
Ser4MCCR0 &= ~MCCR0_MCE;
}
/*
* Our methods.
*/
static struct mcp_ops mcp_sa11x0 = {
.set_telecom_divisor = mcp_sa11x0_set_telecom_divisor,
.set_audio_divisor = mcp_sa11x0_set_audio_divisor,
.reg_write = mcp_sa11x0_write,
.reg_read = mcp_sa11x0_read,
.enable = mcp_sa11x0_enable,
.disable = mcp_sa11x0_disable,
};
static int mcp_sa11x0_probe(struct platform_device *pdev)
{
struct mcp_plat_data *data = pdev->dev.platform_data;
struct mcp *mcp;
int ret;
if (!data)
return -ENODEV;
if (!request_mem_region(0x80060000, 0x60, "sa11x0-mcp"))
return -EBUSY;
mcp = mcp_host_alloc(&pdev->dev, sizeof(struct mcp_sa11x0));
if (!mcp) {
ret = -ENOMEM;
goto release;
}
mcp->owner = THIS_MODULE;
mcp->ops = &mcp_sa11x0;
mcp->sclk_rate = data->sclk_rate;
mcp->gpio_base = data->gpio_base;
platform_set_drvdata(pdev, mcp);
if (machine_is_assabet()) {
ASSABET_BCR_set(ASSABET_BCR_CODEC_RST);
}
/*
* Initialise device. Note that we initially
* set the sampling rate to minimum.
*/
Ser4MCSR = -1;
Ser4MCCR1 = data->mccr1;
Ser4MCCR0 = data->mccr0 | 0x7f7f;
/*
* Calculate the read/write timeout (us) from the bit clock
* rate. This is the period for 3 64-bit frames. Always
* round this time up.
*/
mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
mcp->sclk_rate;
ret = mcp_host_add(mcp);
if (ret == 0)
goto out;
mcp_host_free(mcp);
release:
release_mem_region(0x80060000, 0x60);
platform_set_drvdata(pdev, NULL);
out:
return ret;
}
static int mcp_sa11x0_remove(struct platform_device *dev)
{
struct mcp *mcp = platform_get_drvdata(dev);
platform_set_drvdata(dev, NULL);
mcp_host_del(mcp);
mcp_host_free(mcp);
release_mem_region(0x80060000, 0x60);
return 0;
}
static int mcp_sa11x0_suspend(struct platform_device *dev, pm_message_t state)
{
struct mcp *mcp = platform_get_drvdata(dev);
priv(mcp)->mccr0 = Ser4MCCR0;
priv(mcp)->mccr1 = Ser4MCCR1;
Ser4MCCR0 &= ~MCCR0_MCE;
return 0;
}
static int mcp_sa11x0_resume(struct platform_device *dev)
{
struct mcp *mcp = platform_get_drvdata(dev);
Ser4MCCR1 = priv(mcp)->mccr1;
Ser4MCCR0 = priv(mcp)->mccr0;
return 0;
}
static struct platform_driver mcp_sa11x0_driver = {
.probe = mcp_sa11x0_probe,
.remove = mcp_sa11x0_remove,
.suspend = mcp_sa11x0_suspend,
.resume = mcp_sa11x0_resume,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
},
};
/*
* This needs re-working
*/
module_platform_driver(mcp_sa11x0_driver);
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
MODULE_LICENSE("GPL");