summaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-designware-master.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-04-30 23:01:02 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-04-30 23:01:02 +0300
commit592fa9532d4e4a7590ca383fd537eb4d53fa585a (patch)
tree48ead2d9a235f00fb2635613b1ed96e6b7d4bd4b /drivers/i2c/busses/i2c-designware-master.c
parentefd8929b9eec1cde120abb36d76dd00ff6711023 (diff)
parenta80f24945fcfdff31bdf04837145e56570741a67 (diff)
downloadlinux-592fa9532d4e4a7590ca383fd537eb4d53fa585a.tar.xz
Merge branch 'i2c/for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: - new drivers for Silicon Labs CP2615 and the HiSilicon I2C unit - bigger refactoring for the MPC driver - support for full software nodes - no need to work around with only properties anymore - we now have 'devm_i2c_add_adapter', too - sub-system wide fixes for the RPM refcounting problem which often caused a leak when an error was encountered during probe - the rest is usual driver updates and improvements * 'i2c/for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (77 commits) i2c: mediatek: Use scl_int_delay_ns to compensate clock-stretching i2c: mediatek: Fix wrong dma sync flag i2c: mediatek: Fix send master code at more than 1MHz i2c: sh7760: fix IRQ error path i2c: i801: Add support for Intel Alder Lake PCH-M i2c: core: Fix spacing error by checkpatch i2c: s3c2410: simplify getting of_device_id match data i2c: nomadik: Fix space errors i2c: iop3xx: Fix coding style issues i2c: amd8111: Fix coding style issues i2c: mpc: Drop duplicate message from devm_platform_ioremap_resource() i2c: mpc: Use device_get_match_data() helper i2c: mpc: Remove CONFIG_PM_SLEEP ifdeffery i2c: mpc: Use devm_clk_get_optional() i2c: mpc: Update license and copyright i2c: mpc: Interrupt driven transfer i2c: sh7760: add IRQ check i2c: rcar: add IRQ check i2c: mlxbf: add IRQ check i2c: jz4780: add IRQ check ...
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-master.c')
-rw-r--r--drivers/i2c/busses/i2c-designware-master.c155
1 files changed, 138 insertions, 17 deletions
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index 873ef38eb1c8..13be1d678c39 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -23,6 +23,10 @@
#include "i2c-designware-core.h"
+#define AMD_TIMEOUT_MIN_US 25
+#define AMD_TIMEOUT_MAX_US 250
+#define AMD_MASTERCFG_MASK GENMASK(15, 0)
+
static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
{
/* Configure Tx/Rx FIFO threshold levels */
@@ -35,10 +39,10 @@ static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
{
- const char *mode_str, *fp_str = "";
u32 comp_param1;
u32 sda_falling_time, scl_falling_time;
struct i2c_timings *t = &dev->timings;
+ const char *fp_str = "";
u32 ic_clk;
int ret;
@@ -78,7 +82,7 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
* difference is the timing parameter values since the registers are
* the same.
*/
- if (t->bus_freq_hz == 1000000) {
+ if (t->bus_freq_hz == I2C_MAX_FAST_MODE_PLUS_FREQ) {
/*
* Check are Fast Mode Plus parameters available. Calculate
* SCL timing parameters for Fast Mode Plus if not set.
@@ -154,22 +158,10 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
ret = i2c_dw_set_sda_hold(dev);
if (ret)
- goto out;
-
- switch (dev->master_cfg & DW_IC_CON_SPEED_MASK) {
- case DW_IC_CON_SPEED_STD:
- mode_str = "Standard Mode";
- break;
- case DW_IC_CON_SPEED_HIGH:
- mode_str = "High Speed Mode";
- break;
- default:
- mode_str = "Fast Mode";
- }
- dev_dbg(dev->dev, "Bus speed: %s%s\n", mode_str, fp_str);
+ return ret;
-out:
- return ret;
+ dev_dbg(dev->dev, "Bus speed: %s\n", i2c_freq_mode_string(t->bus_freq_hz));
+ return 0;
}
/**
@@ -260,6 +252,108 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_MASTER_MASK);
}
+static int i2c_dw_check_stopbit(struct dw_i2c_dev *dev)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read_poll_timeout(dev->map, DW_IC_INTR_STAT, val,
+ !(val & DW_IC_INTR_STOP_DET),
+ 1100, 20000);
+ if (ret)
+ dev_err(dev->dev, "i2c timeout error %d\n", ret);
+
+ return ret;
+}
+
+static int i2c_dw_status(struct dw_i2c_dev *dev)
+{
+ int status;
+
+ status = i2c_dw_wait_bus_not_busy(dev);
+ if (status)
+ return status;
+
+ return i2c_dw_check_stopbit(dev);
+}
+
+/*
+ * Initiate and continue master read/write transaction with polling
+ * based transfer routine afterward write messages into the Tx buffer.
+ */
+static int amd_i2c_dw_xfer_quirk(struct i2c_adapter *adap, struct i2c_msg *msgs, int num_msgs)
+{
+ struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
+ int msg_wrt_idx, msg_itr_lmt, buf_len, data_idx;
+ int cmd = 0, status;
+ u8 *tx_buf;
+ u32 val;
+
+ /*
+ * In order to enable the interrupt for UCSI i.e. AMD NAVI GPU card,
+ * it is mandatory to set the right value in specific register
+ * (offset:0x474) as per the hardware IP specification.
+ */
+ regmap_write(dev->map, AMD_UCSI_INTR_REG, AMD_UCSI_INTR_EN);
+
+ dev->msgs = msgs;
+ dev->msgs_num = num_msgs;
+ i2c_dw_xfer_init(dev);
+ i2c_dw_disable_int(dev);
+
+ /* Initiate messages read/write transaction */
+ for (msg_wrt_idx = 0; msg_wrt_idx < num_msgs; msg_wrt_idx++) {
+ tx_buf = msgs[msg_wrt_idx].buf;
+ buf_len = msgs[msg_wrt_idx].len;
+
+ if (!(msgs[msg_wrt_idx].flags & I2C_M_RD))
+ regmap_write(dev->map, DW_IC_TX_TL, buf_len - 1);
+ /*
+ * Initiate the i2c read/write transaction of buffer length,
+ * and poll for bus busy status. For the last message transfer,
+ * update the command with stopbit enable.
+ */
+ for (msg_itr_lmt = buf_len; msg_itr_lmt > 0; msg_itr_lmt--) {
+ if (msg_wrt_idx == num_msgs - 1 && msg_itr_lmt == 1)
+ cmd |= BIT(9);
+
+ if (msgs[msg_wrt_idx].flags & I2C_M_RD) {
+ /* Due to hardware bug, need to write the same command twice. */
+ regmap_write(dev->map, DW_IC_DATA_CMD, 0x100);
+ regmap_write(dev->map, DW_IC_DATA_CMD, 0x100 | cmd);
+ if (cmd) {
+ regmap_write(dev->map, DW_IC_TX_TL, 2 * (buf_len - 1));
+ regmap_write(dev->map, DW_IC_RX_TL, 2 * (buf_len - 1));
+ /*
+ * Need to check the stop bit. However, it cannot be
+ * detected from the registers so we check it always
+ * when read/write the last byte.
+ */
+ status = i2c_dw_status(dev);
+ if (status)
+ return status;
+
+ for (data_idx = 0; data_idx < buf_len; data_idx++) {
+ regmap_read(dev->map, DW_IC_DATA_CMD, &val);
+ tx_buf[data_idx] = val;
+ }
+ status = i2c_dw_check_stopbit(dev);
+ if (status)
+ return status;
+ }
+ } else {
+ regmap_write(dev->map, DW_IC_DATA_CMD, *tx_buf++ | cmd);
+ usleep_range(AMD_TIMEOUT_MIN_US, AMD_TIMEOUT_MAX_US);
+ }
+ }
+ status = i2c_dw_check_stopbit(dev);
+ if (status)
+ return status;
+ }
+
+ return 0;
+}
+
/*
* Initiate (and continue) low level master read/write transaction.
* This function is only called from i2c_dw_isr, and pumping i2c_msg
@@ -463,6 +557,16 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
pm_runtime_get_sync(dev->dev);
+ /*
+ * Initiate I2C message transfer when AMD NAVI GPU card is enabled,
+ * As it is polling based transfer mechanism, which does not support
+ * interrupt based functionalities of existing DesignWare driver.
+ */
+ if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU) {
+ ret = amd_i2c_dw_xfer_quirk(adap, msgs, num);
+ goto done_nolock;
+ }
+
if (dev_WARN_ONCE(dev->dev, dev->suspended, "Transfer while suspended\n")) {
ret = -ESHUTDOWN;
goto done_nolock;
@@ -739,6 +843,20 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
return 0;
}
+static int amd_i2c_adap_quirk(struct dw_i2c_dev *dev)
+{
+ struct i2c_adapter *adap = &dev->adapter;
+ int ret;
+
+ pm_runtime_get_noresume(dev->dev);
+ ret = i2c_add_numbered_adapter(adap);
+ if (ret)
+ dev_err(dev->dev, "Failed to add adapter: %d\n", ret);
+ pm_runtime_put_noidle(dev->dev);
+
+ return ret;
+}
+
int i2c_dw_probe_master(struct dw_i2c_dev *dev)
{
struct i2c_adapter *adap = &dev->adapter;
@@ -775,6 +893,9 @@ int i2c_dw_probe_master(struct dw_i2c_dev *dev)
adap->dev.parent = dev->dev;
i2c_set_adapdata(adap, dev);
+ if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU)
+ return amd_i2c_adap_quirk(dev);
+
if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
irq_flags = IRQF_NO_SUSPEND;
} else {