Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'i2c-embedded/for-3.3' of git://git.pengutronix.de/git/wsa/linux-2.6
i2c bugfix from Wolfram Sang:
"This patch fixes a wrong assumption in the mxs-i2c-driver about a
command queue being done. Without it, we have seen races when the
bus was under load."
* 'i2c-embedded/for-3.3' of git://git.pengutronix.de/git/wsa/linux-2.6:
i2c: mxs: only flag completion when queue is completely done
+10
-3
+10
-3
drivers/i2c/busses/i2c-mxs.c
+10
-3
drivers/i2c/busses/i2c-mxs.c
···
72
72
73
73
#define MXS_I2C_QUEUESTAT (0x70)
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74
#define MXS_I2C_QUEUESTAT_RD_QUEUE_EMPTY 0x00002000
75
+
#define MXS_I2C_QUEUESTAT_WRITE_QUEUE_CNT_MASK 0x0000001F
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#define MXS_I2C_QUEUECMD (0x80)
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78
···
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219
int ret;
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220
int flags;
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223
-
init_completion(&i2c->cmd_complete);
224
-
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222
dev_dbg(i2c->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
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223
msg->addr, msg->len, msg->flags, stop);
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224
228
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if (msg->len == 0)
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return -EINVAL;
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+
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+
init_completion(&i2c->cmd_complete);
230
229
231
230
flags = stop ? MXS_I2C_CTRL0_POST_SEND_STOP : 0;
232
231
···
287
286
{
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287
struct mxs_i2c_dev *i2c = dev_id;
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u32 stat = readl(i2c->regs + MXS_I2C_CTRL1) & MXS_I2C_IRQ_MASK;
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+
bool is_last_cmd;
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if (!stat)
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return IRQ_NONE;
···
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300
else
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301
i2c->cmd_err = 0;
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302
305
-
complete(&i2c->cmd_complete);
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+
is_last_cmd = (readl(i2c->regs + MXS_I2C_QUEUESTAT) &
304
+
MXS_I2C_QUEUESTAT_WRITE_QUEUE_CNT_MASK) == 0;
305
+
306
+
if (is_last_cmd || i2c->cmd_err)
307
+
complete(&i2c->cmd_complete);
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309
writel(stat, i2c->regs + MXS_I2C_CTRL1_CLR);
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+
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311
return IRQ_HANDLED;
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}
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