summaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-designware-core.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-05 09:31:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-05 09:31:03 -0700
commit00341b5301009ba6f36ee3298e69b649ac5540ff (patch)
tree0f0cdcabd20b2834f30b67b50795c49989ced65a /drivers/i2c/busses/i2c-designware-core.c
parent45d9a2220f6004b47c362cc7fc7cf9a73cb6353a (diff)
parentb720423a2627f045133bec39a31fe2bc0dab86f3 (diff)
Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: "Highlights: - OF and ACPI helpers are now included in the core, and not in external files anymore. This removes dependency problems for modules and is cleaner, in general. - mv64xxx-driver gains fifo usage to support mv78230 - imx-driver overhaul to support VF610 - various cleanups, most notably related to devm_* and CONFIG_PM usage - driver bugfixes and smaller feature additions" * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (51 commits) i2c: rcar: add rcar-H2 support i2c: sirf: retry 3 times as sometimes we get random noack and timeout i2c: sirf: support reverse direction of address i2c: sirf: fix the typo for setting bitrate to less than 100k i2c: sirf: we need to wait I2C_RESET status in resume i2c: sirf: reset i2c controller early after we get a noack i2c: designware: get SDA hold time, HCNT and LCNT configuration from ACPI i2c: designware: make HCNT/LCNT values configurable i2c: mpc: cleanup clock API use i2c: pnx: fix error return code in i2c_pnx_probe() i2c: ismt: add error return code in probe() i2c: mv64xxx: fix typo in binding documentation i2c: imx: use exact SoC revision to document binding i2c: move ACPI helpers into the core i2c: move OF helpers into the core i2c: mv64xxx: Fix timing issue on Armada XP (errata FE-8471889) i2c: mv64xxx: Add I2C Transaction Generator support i2c: powermac: fix return path on error Documentation: i2c: Fix example in instantiating-devices i2c: tiny-usb: do not use stack as URB transfer_buffer ...
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-core.c')
-rw-r--r--drivers/i2c/busses/i2c-designware-core.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index ad46616de29e..dbecf08399f8 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -317,6 +317,12 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
47, /* tLOW = 4.7 us */
3, /* tf = 0.3 us */
0); /* No offset */
+
+ /* Allow platforms to specify the ideal HCNT and LCNT values */
+ if (dev->ss_hcnt && dev->ss_lcnt) {
+ hcnt = dev->ss_hcnt;
+ lcnt = dev->ss_lcnt;
+ }
dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT);
dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT);
dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
@@ -331,6 +337,11 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
13, /* tLOW = 1.3 us */
3, /* tf = 0.3 us */
0); /* No offset */
+
+ if (dev->fs_hcnt && dev->fs_lcnt) {
+ hcnt = dev->fs_hcnt;
+ lcnt = dev->fs_lcnt;
+ }
dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT);
dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
@@ -416,6 +427,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
u32 addr = msgs[dev->msg_write_idx].addr;
u32 buf_len = dev->tx_buf_len;
u8 *buf = dev->tx_buf;
+ bool need_restart = false;
intr_mask = DW_IC_INTR_DEFAULT_MASK;
@@ -443,6 +455,14 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
/* new i2c_msg */
buf = msgs[dev->msg_write_idx].buf;
buf_len = msgs[dev->msg_write_idx].len;
+
+ /* If both IC_EMPTYFIFO_HOLD_MASTER_EN and
+ * IC_RESTART_EN are set, we must manually
+ * set restart bit between messages.
+ */
+ if ((dev->master_cfg & DW_IC_CON_RESTART_EN) &&
+ (dev->msg_write_idx > 0))
+ need_restart = true;
}
tx_limit = dev->tx_fifo_depth - dw_readl(dev, DW_IC_TXFLR);
@@ -461,6 +481,11 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
buf_len == 1)
cmd |= BIT(9);
+ if (need_restart) {
+ cmd |= BIT(10);
+ need_restart = false;
+ }
+
if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
/* avoid rx buffer overrun */