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authorNikolaus Voss <n.voss@weinmann.de>2011-11-08 11:49:24 +0100
committerWolfram Sang <w.sang@pengutronix.de>2012-09-12 14:49:12 +0200
commita879e9c34b93ee43f5caa7f94eb17e7af4f6ef50 (patch)
treebef8ff00920554f7930ef47bcfebbab4f03d3c01 /drivers/i2c/busses/i2c-at91.c
parentaf2a5f09fb6d317a0ec4b5026cd50f0b49a60419 (diff)
i2c: at91: remove old polling driver
It will get replaced by a superior one. Safe to remove since this one depends on BROKEN anyhow. Signed-off-by: Nikolaus Voss <n.voss@weinmann.de> Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com> Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com> [wsa: added commit message] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Diffstat (limited to 'drivers/i2c/busses/i2c-at91.c')
-rw-r--r--drivers/i2c/busses/i2c-at91.c315
1 files changed, 0 insertions, 315 deletions
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
deleted file mode 100644
index e24484beef0..00000000000
--- a/drivers/i2c/busses/i2c-at91.c
+++ /dev/null
@@ -1,315 +0,0 @@
-/*
- i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
-
- Copyright (C) 2004 Rick Bronson
- Converted to 2.6 by Andrew Victor <andrew@sanpeople.com>
-
- Borrowed heavily from original work by:
- Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
-
- 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, or
- (at your option) any later version.
-*/
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/err.h>
-#include <linux/slab.h>
-#include <linux/types.h>
-#include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/init.h>
-#include <linux/clk.h>
-#include <linux/platform_device.h>
-#include <linux/io.h>
-
-#include <mach/at91_twi.h>
-#include <mach/board.h>
-#include <mach/cpu.h>
-
-#define TWI_CLOCK 100000 /* Hz. max 400 Kbits/sec */
-
-
-static struct clk *twi_clk;
-static void __iomem *twi_base;
-
-#define at91_twi_read(reg) __raw_readl(twi_base + (reg))
-#define at91_twi_write(reg, val) __raw_writel((val), twi_base + (reg))
-
-
-/*
- * Initialize the TWI hardware registers.
- */
-static void __devinit at91_twi_hwinit(void)
-{
- unsigned long cdiv, ckdiv;
-
- at91_twi_write(AT91_TWI_IDR, 0xffffffff); /* Disable all interrupts */
- at91_twi_write(AT91_TWI_CR, AT91_TWI_SWRST); /* Reset peripheral */
- at91_twi_write(AT91_TWI_CR, AT91_TWI_MSEN); /* Set Master mode */
-
- /* Calcuate clock dividers */
- cdiv = (clk_get_rate(twi_clk) / (2 * TWI_CLOCK)) - 3;
- cdiv = cdiv + 1; /* round up */
- ckdiv = 0;
- while (cdiv > 255) {
- ckdiv++;
- cdiv = cdiv >> 1;
- }
-
- if (cpu_is_at91rm9200()) { /* AT91RM9200 Errata #22 */
- if (ckdiv > 5) {
- printk(KERN_ERR "AT91 I2C: Invalid TWI_CLOCK value!\n");
- ckdiv = 5;
- }
- }
-
- at91_twi_write(AT91_TWI_CWGR, (ckdiv << 16) | (cdiv << 8) | cdiv);
-}
-
-/*
- * Poll the i2c status register until the specified bit is set.
- * Returns 0 if timed out (100 msec).
- */
-static short at91_poll_status(unsigned long bit)
-{
- int loop_cntr = 10000;
-
- do {
- udelay(10);
- } while (!(at91_twi_read(AT91_TWI_SR) & bit) && (--loop_cntr > 0));
-
- return (loop_cntr > 0);
-}
-
-static int xfer_read(struct i2c_adapter *adap, unsigned char *buf, int length)
-{
- /* Send Start */
- at91_twi_write(AT91_TWI_CR, AT91_TWI_START);
-
- /* Read data */
- while (length--) {
- if (!length) /* need to send Stop before reading last byte */
- at91_twi_write(AT91_TWI_CR, AT91_TWI_STOP);
- if (!at91_poll_status(AT91_TWI_RXRDY)) {
- dev_dbg(&adap->dev, "RXRDY timeout\n");
- return -ETIMEDOUT;
- }
- *buf++ = (at91_twi_read(AT91_TWI_RHR) & 0xff);
- }
-
- return 0;
-}
-
-static int xfer_write(struct i2c_adapter *adap, unsigned char *buf, int length)
-{
- /* Load first byte into transmitter */
- at91_twi_write(AT91_TWI_THR, *buf++);
-
- /* Send Start */
- at91_twi_write(AT91_TWI_CR, AT91_TWI_START);
-
- do {
- if (!at91_poll_status(AT91_TWI_TXRDY)) {
- dev_dbg(&adap->dev, "TXRDY timeout\n");
- return -ETIMEDOUT;
- }
-
- length--; /* byte was transmitted */
-
- if (length > 0) /* more data to send? */
- at91_twi_write(AT91_TWI_THR, *buf++);
- } while (length);
-
- /* Send Stop */
- at91_twi_write(AT91_TWI_CR, AT91_TWI_STOP);
-
- return 0;
-}
-
-/*
- * Generic i2c master transfer entrypoint.
- *
- * Note: We do not use Atmel's feature of storing the "internal device address".
- * Instead the "internal device address" has to be written using a separate
- * i2c message.
- * http://lists.arm.linux.org.uk/pipermail/linux-arm-kernel/2004-September/024411.html
- */
-static int at91_xfer(struct i2c_adapter *adap, struct i2c_msg *pmsg, int num)
-{
- int i, ret;
-
- dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num);
-
- for (i = 0; i < num; i++) {
- dev_dbg(&adap->dev, " #%d: %sing %d byte%s %s 0x%02x\n", i,
- pmsg->flags & I2C_M_RD ? "read" : "writ",
- pmsg->len, pmsg->len > 1 ? "s" : "",
- pmsg->flags & I2C_M_RD ? "from" : "to", pmsg->addr);
-
- at91_twi_write(AT91_TWI_MMR, (pmsg->addr << 16)
- | ((pmsg->flags & I2C_M_RD) ? AT91_TWI_MREAD : 0));
-
- if (pmsg->len && pmsg->buf) { /* sanity check */
- if (pmsg->flags & I2C_M_RD)
- ret = xfer_read(adap, pmsg->buf, pmsg->len);
- else
- ret = xfer_write(adap, pmsg->buf, pmsg->len);
-
- if (ret)
- return ret;
-
- /* Wait until transfer is finished */
- if (!at91_poll_status(AT91_TWI_TXCOMP)) {
- dev_dbg(&adap->dev, "TXCOMP timeout\n");
- return -ETIMEDOUT;
- }
- }
- dev_dbg(&adap->dev, "transfer complete\n");
- pmsg++; /* next message */
- }
- return i;
-}
-
-/*
- * Return list of supported functionality.
- */
-static u32 at91_func(struct i2c_adapter *adapter)
-{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
-}
-
-static struct i2c_algorithm at91_algorithm = {
- .master_xfer = at91_xfer,
- .functionality = at91_func,
-};
-
-/*
- * Main initialization routine.
- */
-static int __devinit at91_i2c_probe(struct platform_device *pdev)
-{
- struct i2c_adapter *adapter;
- struct resource *res;
- int rc;
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- return -ENXIO;
-
- if (!request_mem_region(res->start, resource_size(res), "at91_i2c"))
- return -EBUSY;
-
- twi_base = ioremap(res->start, resource_size(res));
- if (!twi_base) {
- rc = -ENOMEM;
- goto fail0;
- }
-
- twi_clk = clk_get(NULL, "twi_clk");
- if (IS_ERR(twi_clk)) {
- dev_err(&pdev->dev, "no clock defined\n");
- rc = -ENODEV;
- goto fail1;
- }
-
- adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
- if (adapter == NULL) {
- dev_err(&pdev->dev, "can't allocate inteface!\n");
- rc = -ENOMEM;
- goto fail2;
- }
- snprintf(adapter->name, sizeof(adapter->name), "AT91");
- adapter->algo = &at91_algorithm;
- adapter->class = I2C_CLASS_HWMON;
- adapter->dev.parent = &pdev->dev;
- /* adapter->id == 0 ... only one TWI controller for now */
-
- platform_set_drvdata(pdev, adapter);
-
- clk_enable(twi_clk); /* enable peripheral clock */
- at91_twi_hwinit(); /* initialize TWI controller */
-
- rc = i2c_add_numbered_adapter(adapter);
- if (rc) {
- dev_err(&pdev->dev, "Adapter %s registration failed\n",
- adapter->name);
- goto fail3;
- }
-
- dev_info(&pdev->dev, "AT91 i2c bus driver.\n");
- return 0;
-
-fail3:
- platform_set_drvdata(pdev, NULL);
- kfree(adapter);
- clk_disable(twi_clk);
-fail2:
- clk_put(twi_clk);
-fail1:
- iounmap(twi_base);
-fail0:
- release_mem_region(res->start, resource_size(res));
-
- return rc;
-}
-
-static int __devexit at91_i2c_remove(struct platform_device *pdev)
-{
- struct i2c_adapter *adapter = platform_get_drvdata(pdev);
- struct resource *res;
- int rc;
-
- rc = i2c_del_adapter(adapter);
- platform_set_drvdata(pdev, NULL);
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- iounmap(twi_base);
- release_mem_region(res->start, resource_size(res));
-
- clk_disable(twi_clk); /* disable peripheral clock */
- clk_put(twi_clk);
-
- return rc;
-}
-
-#ifdef CONFIG_PM
-
-/* NOTE: could save a few mA by keeping clock off outside of at91_xfer... */
-
-static int at91_i2c_suspend(struct device *dev)
-{
- clk_disable(twi_clk);
- return 0;
-}
-
-static int at91_i2c_resume(struct device *dev)
-{
- return clk_enable(twi_clk);
-}
-
-static SIMPLE_DEV_PM_OPS(at91_i2c_pm, at91_i2c_suspend, at91_i2c_resume);
-#define AT91_I2C_PM (&at91_i2c_pm)
-
-#else
-#define AT91_I2C_PM NULL
-#endif
-
-static struct platform_driver at91_i2c_driver = {
- .probe = at91_i2c_probe,
- .remove = __devexit_p(at91_i2c_remove),
- .driver = {
- .name = "at91_i2c",
- .owner = THIS_MODULE,
- .pm = AT91_I2C_PM,
- },
-};
-
-module_platform_driver(at91_i2c_driver);
-
-MODULE_AUTHOR("Rick Bronson");
-MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:at91_i2c");