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-rw-r--r--drivers/i2c/busses/i2c-i801.c19
-rw-r--r--drivers/i2c/busses/i2c-rcar.c41
-rw-r--r--drivers/i2c/busses/i2c-riic.c2
-rw-r--r--drivers/i2c/i2c-core.h2
-rw-r--r--drivers/mfd/tps6586x.c50
-rw-r--r--include/linux/reboot.h3
-rw-r--r--kernel/reboot.c4
7 files changed, 78 insertions, 43 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 1d855258a45d..9bd712eafa8e 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -679,15 +679,11 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
return result ? priv->status : -ETIMEDOUT;
}
- for (i = 1; i <= len; i++) {
- if (i == len && read_write == I2C_SMBUS_READ)
- smbcmd |= SMBHSTCNT_LAST_BYTE;
- outb_p(smbcmd, SMBHSTCNT(priv));
-
- if (i == 1)
- outb_p(inb(SMBHSTCNT(priv)) | SMBHSTCNT_START,
- SMBHSTCNT(priv));
+ if (len == 1 && read_write == I2C_SMBUS_READ)
+ smbcmd |= SMBHSTCNT_LAST_BYTE;
+ outb_p(smbcmd | SMBHSTCNT_START, SMBHSTCNT(priv));
+ for (i = 1; i <= len; i++) {
status = i801_wait_byte_done(priv);
if (status)
return status;
@@ -710,9 +706,12 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
data->block[0] = len;
}
- /* Retrieve/store value in SMBBLKDAT */
- if (read_write == I2C_SMBUS_READ)
+ if (read_write == I2C_SMBUS_READ) {
data->block[i] = inb_p(SMBBLKDAT(priv));
+ if (i == len - 1)
+ outb_p(smbcmd | SMBHSTCNT_LAST_BYTE, SMBHSTCNT(priv));
+ }
+
if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
outb_p(data->block[i+1], SMBBLKDAT(priv));
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index a32a93f9a60d..5e97635faf78 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -291,45 +291,40 @@ static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv)
ick = rate / (cdf + 1);
/*
- * it is impossible to calculate large scale
- * number on u32. separate it
+ * It is impossible to calculate a large scale number on u32. Separate it.
*
* F[(ticf + tr + intd) * ick] with sum = (ticf + tr + intd)
* = F[sum * ick / 1000000000]
* = F[(ick / 1000000) * sum / 1000]
*/
sum = t.scl_fall_ns + t.scl_rise_ns + t.scl_int_delay_ns;
- round = (ick + 500000) / 1000000 * sum;
- round = (round + 500) / 1000;
+ round = DIV_ROUND_CLOSEST(ick, 1000000);
+ round = DIV_ROUND_CLOSEST(round * sum, 1000);
/*
- * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
- *
- * Calculation result (= SCL) should be less than
- * bus_speed for hardware safety
- *
- * We could use something along the lines of
- * div = ick / (bus_speed + 1) + 1;
- * scgd = (div - 20 - round + 7) / 8;
- * scl = ick / (20 + (scgd * 8) + round);
- * (not fully verified) but that would get pretty involved
+ * SCL = ick / (20 + 8 * SCGD + F[(ticf + tr + intd) * ick])
+ * 20 + 8 * SCGD + F[...] = ick / SCL
+ * SCGD = ((ick / SCL) - 20 - F[...]) / 8
+ * Result (= SCL) should be less than bus_speed for hardware safety
*/
- for (scgd = 0; scgd < 0x40; scgd++) {
- scl = ick / (20 + (scgd * 8) + round);
- if (scl <= t.bus_freq_hz)
- goto scgd_find;
- }
- dev_err(dev, "it is impossible to calculate best SCL\n");
- return -EIO;
+ scgd = DIV_ROUND_UP(ick, t.bus_freq_hz ?: 1);
+ scgd = DIV_ROUND_UP(scgd - 20 - round, 8);
+ scl = ick / (20 + 8 * scgd + round);
+
+ if (scgd > 0x3f)
+ goto err_no_val;
-scgd_find:
- dev_dbg(dev, "clk %d/%d(%lu), round %u, CDF:0x%x, SCGD: 0x%x\n",
+ dev_dbg(dev, "clk %u/%u(%lu), round %u, CDF: %u, SCGD: %u\n",
scl, t.bus_freq_hz, rate, round, cdf, scgd);
/* keep icccr value */
priv->icccr = scgd << cdf_width | cdf;
return 0;
+
+err_no_val:
+ dev_err(dev, "it is impossible to calculate best SCL\n");
+ return -EINVAL;
}
/*
diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c
index f0ee8871d5ae..e43ff483c56e 100644
--- a/drivers/i2c/busses/i2c-riic.c
+++ b/drivers/i2c/busses/i2c-riic.c
@@ -313,7 +313,7 @@ static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t)
* frequency with only 62 clock ticks max (31 high, 31 low).
* Aim for a duty of 60% LOW, 40% HIGH.
*/
- total_ticks = DIV_ROUND_UP(rate, t->bus_freq_hz);
+ total_ticks = DIV_ROUND_UP(rate, t->bus_freq_hz ?: 1);
for (cks = 0; cks < 7; cks++) {
/*
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 1247e6e6e975..05b8b8dfa9bd 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -29,7 +29,7 @@ int i2c_dev_irq_from_resources(const struct resource *resources,
*/
static inline bool i2c_in_atomic_xfer_mode(void)
{
- return system_state > SYSTEM_RUNNING && irqs_disabled();
+ return system_state > SYSTEM_RUNNING && !preemptible();
}
static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
diff --git a/drivers/mfd/tps6586x.c b/drivers/mfd/tps6586x.c
index 55675ceedcd3..7e8160b94784 100644
--- a/drivers/mfd/tps6586x.c
+++ b/drivers/mfd/tps6586x.c
@@ -22,6 +22,7 @@
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
+#include <linux/reboot.h>
#include <linux/regmap.h>
#include <linux/of.h>
@@ -29,6 +30,7 @@
#include <linux/mfd/tps6586x.h>
#define TPS6586X_SUPPLYENE 0x14
+#define SOFT_RST_BIT BIT(0)
#define EXITSLREQ_BIT BIT(1)
#define SLEEP_MODE_BIT BIT(3)
@@ -457,13 +459,34 @@ static const struct regmap_config tps6586x_regmap_config = {
.cache_type = REGCACHE_RBTREE,
};
-static struct device *tps6586x_dev;
-static void tps6586x_power_off(void)
+static int tps6586x_power_off_handler(struct sys_off_data *data)
{
- if (tps6586x_clr_bits(tps6586x_dev, TPS6586X_SUPPLYENE, EXITSLREQ_BIT))
- return;
+ int ret;
+
+ /* Put the PMIC into sleep state. This takes at least 20ms. */
+ ret = tps6586x_clr_bits(data->dev, TPS6586X_SUPPLYENE, EXITSLREQ_BIT);
+ if (ret)
+ return notifier_from_errno(ret);
+
+ ret = tps6586x_set_bits(data->dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
+ if (ret)
+ return notifier_from_errno(ret);
+
+ mdelay(50);
+ return notifier_from_errno(-ETIME);
+}
+
+static int tps6586x_restart_handler(struct sys_off_data *data)
+{
+ int ret;
+
+ /* Put the PMIC into hard reboot state. This takes at least 20ms. */
+ ret = tps6586x_set_bits(data->dev, TPS6586X_SUPPLYENE, SOFT_RST_BIT);
+ if (ret)
+ return notifier_from_errno(ret);
- tps6586x_set_bits(tps6586x_dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
+ mdelay(50);
+ return notifier_from_errno(-ETIME);
}
static void tps6586x_print_version(struct i2c_client *client, int version)
@@ -559,9 +582,20 @@ static int tps6586x_i2c_probe(struct i2c_client *client)
goto err_add_devs;
}
- if (pdata->pm_off && !pm_power_off) {
- tps6586x_dev = &client->dev;
- pm_power_off = tps6586x_power_off;
+ if (pdata->pm_off) {
+ ret = devm_register_power_off_handler(&client->dev, &tps6586x_power_off_handler,
+ NULL);
+ if (ret) {
+ dev_err(&client->dev, "register power off handler failed: %d\n", ret);
+ goto err_add_devs;
+ }
+
+ ret = devm_register_restart_handler(&client->dev, &tps6586x_restart_handler,
+ NULL);
+ if (ret) {
+ dev_err(&client->dev, "register restart handler failed: %d\n", ret);
+ goto err_add_devs;
+ }
}
return 0;
diff --git a/include/linux/reboot.h b/include/linux/reboot.h
index 2b6bb593be5b..c4cc3b89ced1 100644
--- a/include/linux/reboot.h
+++ b/include/linux/reboot.h
@@ -129,11 +129,14 @@ enum sys_off_mode {
* @cb_data: User's callback data.
* @cmd: Command string. Currently used only by the sys-off restart mode,
* NULL otherwise.
+ * @dev: Device of the sys-off handler. Only if known (devm_register_*),
+ * NULL otherwise.
*/
struct sys_off_data {
int mode;
void *cb_data;
const char *cmd;
+ struct device *dev;
};
struct sys_off_handler *
diff --git a/kernel/reboot.c b/kernel/reboot.c
index 3bba88c7ffc6..395a0ea3c7a8 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -55,6 +55,7 @@ struct sys_off_handler {
enum sys_off_mode mode;
bool blocking;
void *list;
+ struct device *dev;
};
/*
@@ -74,6 +75,7 @@ void __weak (*pm_power_off)(void);
void emergency_restart(void)
{
kmsg_dump(KMSG_DUMP_EMERG);
+ system_state = SYSTEM_RESTART;
machine_emergency_restart();
}
EXPORT_SYMBOL_GPL(emergency_restart);
@@ -323,6 +325,7 @@ static int sys_off_notify(struct notifier_block *nb,
data.cb_data = handler->cb_data;
data.mode = mode;
data.cmd = cmd;
+ data.dev = handler->dev;
return handler->sys_off_cb(&data);
}
@@ -510,6 +513,7 @@ int devm_register_sys_off_handler(struct device *dev,
handler = register_sys_off_handler(mode, priority, callback, cb_data);
if (IS_ERR(handler))
return PTR_ERR(handler);
+ handler->dev = dev;
return devm_add_action_or_reset(dev, devm_unregister_sys_off_handler,
handler);