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authorPeter Milne <peter.milne@d-tacq.com>2006-07-01 11:03:20 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2006-07-12 18:43:06 -0400
commit39288e1ac10b3b9a68a629be67d81a0b53512c4e (patch)
tree6919a260a100cf19581d1641b22d1d982080528b /drivers/i2c
parent2369df933f1c632ec3f230774019e37c3969b7ec (diff)
[PATCH] i2c-iop3xx: Avoid addressing self
Avoid addressing self when sending a slave address. Follows instruction in Intel 80331/80321 manuals. Ignoring this worked previously on 80321, but causes a hang on i2cdetect on 80331. Signed-off-by: Peter Milne <peter.milne@d-tacq.com> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-iop3xx.c17
-rw-r--r--drivers/i2c/busses/i2c-iop3xx.h2
2 files changed, 11 insertions, 8 deletions
diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c
index aca7e1668605..48c56939c861 100644
--- a/drivers/i2c/busses/i2c-iop3xx.c
+++ b/drivers/i2c/busses/i2c-iop3xx.c
@@ -21,6 +21,9 @@
21 * - Make it work with IXP46x chips 21 * - Make it work with IXP46x chips
22 * - Cleanup function names, coding style, etc 22 * - Cleanup function names, coding style, etc
23 * 23 *
24 * - writing to slave address causes latchup on iop331.
25 * fix: driver refuses to address self.
26 *
24 * This program is free software; you can redistribute it and/or modify 27 * This program is free software; you can redistribute it and/or modify
25 * it under the terms of the GNU General Public License as published by 28 * it under the terms of the GNU General Public License as published by
26 * the Free Software Foundation, version 2. 29 * the Free Software Foundation, version 2.
@@ -73,12 +76,6 @@ iop3xx_i2c_reset(struct i2c_algo_iop3xx_data *iop3xx_adap)
73} 76}
74 77
75static void 78static void
76iop3xx_i2c_set_slave_addr(struct i2c_algo_iop3xx_data *iop3xx_adap)
77{
78 __raw_writel(MYSAR, iop3xx_adap->ioaddr + SAR_OFFSET);
79}
80
81static void
82iop3xx_i2c_enable(struct i2c_algo_iop3xx_data *iop3xx_adap) 79iop3xx_i2c_enable(struct i2c_algo_iop3xx_data *iop3xx_adap)
83{ 80{
84 u32 cr = IOP3XX_ICR_GCD | IOP3XX_ICR_SCLEN | IOP3XX_ICR_UE; 81 u32 cr = IOP3XX_ICR_GCD | IOP3XX_ICR_SCLEN | IOP3XX_ICR_UE;
@@ -248,6 +245,13 @@ iop3xx_i2c_send_target_addr(struct i2c_algo_iop3xx_data *iop3xx_adap,
248 int status; 245 int status;
249 int rc; 246 int rc;
250 247
248 /* avoid writing to my slave address (hangs on 80331),
249 * forbidden in Intel developer manual
250 */
251 if (msg->addr == MYSAR) {
252 return -EBUSY;
253 }
254
251 __raw_writel(iic_cook_addr(msg), iop3xx_adap->ioaddr + DBR_OFFSET); 255 __raw_writel(iic_cook_addr(msg), iop3xx_adap->ioaddr + DBR_OFFSET);
252 256
253 cr &= ~(IOP3XX_ICR_MSTOP | IOP3XX_ICR_NACK); 257 cr &= ~(IOP3XX_ICR_MSTOP | IOP3XX_ICR_NACK);
@@ -498,7 +502,6 @@ iop3xx_i2c_probe(struct platform_device *pdev)
498 spin_lock_init(&adapter_data->lock); 502 spin_lock_init(&adapter_data->lock);
499 503
500 iop3xx_i2c_reset(adapter_data); 504 iop3xx_i2c_reset(adapter_data);
501 iop3xx_i2c_set_slave_addr(adapter_data);
502 iop3xx_i2c_enable(adapter_data); 505 iop3xx_i2c_enable(adapter_data);
503 506
504 platform_set_drvdata(pdev, new_adapter); 507 platform_set_drvdata(pdev, new_adapter);
diff --git a/drivers/i2c/busses/i2c-iop3xx.h b/drivers/i2c/busses/i2c-iop3xx.h
index e46ebaea7b1e..8485861f6a36 100644
--- a/drivers/i2c/busses/i2c-iop3xx.h
+++ b/drivers/i2c/busses/i2c-iop3xx.h
@@ -80,7 +80,7 @@
80#define IOP3XX_GPOD_I2C0 0x00c0 /* clear these bits to enable ch0 */ 80#define IOP3XX_GPOD_I2C0 0x00c0 /* clear these bits to enable ch0 */
81#define IOP3XX_GPOD_I2C1 0x0030 /* clear these bits to enable ch1 */ 81#define IOP3XX_GPOD_I2C1 0x0030 /* clear these bits to enable ch1 */
82 82
83#define MYSAR 0x02 /* SWAG a suitable slave address */ 83#define MYSAR 0 /* default slave address */
84 84
85#define I2C_ERR 321 85#define I2C_ERR 321
86#define I2C_ERR_BERR (I2C_ERR+0) 86#define I2C_ERR_BERR (I2C_ERR+0)