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authorLinus Torvalds2015-04-15 03:10:45 +0200
committerLinus Torvalds2015-04-15 03:10:45 +0200
commitc3a416a669eb83cfa9ccb52db030e72d654bd105 (patch)
tree518d00dc803fbb7d3772fc26a78b6bf3b797baf3 /drivers/i2c/i2c-core.c
parentMerge tag 'vfio-v4.1-rc1' of git://github.com/awilliam/linux-vfio (diff)
parenti2c: xlp9xx: Driver for Netlogic XLP9XX/5XX I2C controller (diff)
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Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: "Most notable: - introducing the i2c_quirk infrastructure. Now, flaws of I2C controllers can be described and the core will check if the flaws collide with the messages to be sent - wait_for_completion return type cleanup series - new drivers for Digicolor, Netlogic XLP, Ingenic JZ4780 - updates to the I2C slave framework which include API changes. Its only user was updated, too. Documentation was finally added - changed dynamic bus numbering for the DT case. This could change bus numbers for users. However, it fixes a collision where dynamic and static busses request the same id. - driver bugfixes, cleanups" * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (52 commits) i2c: xlp9xx: Driver for Netlogic XLP9XX/5XX I2C controller of: Add vendor prefix 'netlogic' i2c: davinci: use ICPFUNC to toggle I2C as gpio for bus recovery i2c: davinci: use bus recovery infrastructure i2c: change input parameter to i2c_adapter for prepare/unprepare_recovery i2c: i2c-mux-gpio: remove error messages for probe deferrals i2c: jz4780: Add i2c bus controller driver for Ingenic JZ4780 i2c: dln2: set the device tree node of the adapter i2c: davinci: fixup wait_for_completion_timeout handling i2c: mpc: Fix ISR return value i2c: slave-eeprom: add more info when to increase the pointer i2c: slave: add documentation for i2c-slave-eeprom Documentation: i2c: describe the new slave mode i2c: slave: rework the slave API i2c: add support for the Digicolor I2C controller i2c: busses with dynamic ids should start after fixed ids for DT of: base: add function to get highest id of an alias stem i2c: designware: Suppress error message if platform_get_irq() < 0 i2c: mpc: assign the correct prescaler from SVR i2c: img-scb: fixup of wait_for_completion_timeout return handling ...
Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r--drivers/i2c/i2c-core.c73
1 files changed, 71 insertions, 2 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index edf274cabe81..68f687733379 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -561,7 +561,7 @@ static int i2c_generic_recovery(struct i2c_adapter *adap)
int i = 0, val = 1, ret = 0;
if (bri->prepare_recovery)
- bri->prepare_recovery(bri);
+ bri->prepare_recovery(adap);
/*
* By this time SCL is high, as we need to give 9 falling-rising edges
@@ -586,7 +586,7 @@ static int i2c_generic_recovery(struct i2c_adapter *adap)
}
if (bri->unprepare_recovery)
- bri->unprepare_recovery(bri);
+ bri->unprepare_recovery(adap);
return ret;
}
@@ -1875,6 +1875,13 @@ static int __init i2c_init(void)
{
int retval;
+ retval = of_alias_get_highest_id("i2c");
+
+ down_write(&__i2c_board_lock);
+ if (retval >= __i2c_first_dynamic_bus_num)
+ __i2c_first_dynamic_bus_num = retval + 1;
+ up_write(&__i2c_board_lock);
+
retval = bus_register(&i2c_bus_type);
if (retval)
return retval;
@@ -1926,6 +1933,65 @@ module_exit(i2c_exit);
* ----------------------------------------------------
*/
+/* Check if val is exceeding the quirk IFF quirk is non 0 */
+#define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk)))
+
+static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg)
+{
+ dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n",
+ err_msg, msg->addr, msg->len,
+ msg->flags & I2C_M_RD ? "read" : "write");
+ return -EOPNOTSUPP;
+}
+
+static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+ const struct i2c_adapter_quirks *q = adap->quirks;
+ int max_num = q->max_num_msgs, i;
+ bool do_len_check = true;
+
+ if (q->flags & I2C_AQ_COMB) {
+ max_num = 2;
+
+ /* special checks for combined messages */
+ if (num == 2) {
+ if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD)
+ return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write");
+
+ if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD))
+ return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read");
+
+ if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr)
+ return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr");
+
+ if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len))
+ return i2c_quirk_error(adap, &msgs[0], "msg too long");
+
+ if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len))
+ return i2c_quirk_error(adap, &msgs[1], "msg too long");
+
+ do_len_check = false;
+ }
+ }
+
+ if (i2c_quirk_exceeded(num, max_num))
+ return i2c_quirk_error(adap, &msgs[0], "too many messages");
+
+ for (i = 0; i < num; i++) {
+ u16 len = msgs[i].len;
+
+ if (msgs[i].flags & I2C_M_RD) {
+ if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len))
+ return i2c_quirk_error(adap, &msgs[i], "msg too long");
+ } else {
+ if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len))
+ return i2c_quirk_error(adap, &msgs[i], "msg too long");
+ }
+ }
+
+ return 0;
+}
+
/**
* __i2c_transfer - unlocked flavor of i2c_transfer
* @adap: Handle to I2C bus
@@ -1943,6 +2009,9 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
unsigned long orig_jiffies;
int ret, try;
+ if (adap->quirks && i2c_check_for_quirks(adap, msgs, num))
+ return -EOPNOTSUPP;
+
/* i2c_trace_msg gets enabled when tracepoint i2c_transfer gets
* enabled. This is an efficient way of keeping the for-loop from
* being executed when not needed.