diff options
Diffstat (limited to 'drivers/i2c/i2c-core-base.c')
-rw-r--r-- | drivers/i2c/i2c-core-base.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index cb6c5cb0df0b..688aa3b5f3ac 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -185,7 +185,7 @@ static int i2c_generic_bus_free(struct i2c_adapter *adap) int i2c_generic_scl_recovery(struct i2c_adapter *adap) { struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; - int i = 0, scl = 1, ret; + int i = 0, scl = 1, ret = 0; if (bri->prepare_recovery) bri->prepare_recovery(adap); @@ -327,6 +327,8 @@ static int i2c_device_probe(struct device *dev) if (client->flags & I2C_CLIENT_HOST_NOTIFY) { dev_dbg(dev, "Using Host Notify IRQ\n"); + /* Keep adapter active when Host Notify is required */ + pm_runtime_get_sync(&client->adapter->dev); irq = i2c_smbus_host_notify_to_irq(client); } else if (dev->of_node) { irq = of_irq_get_byname(dev->of_node, "irq"); @@ -431,6 +433,8 @@ static int i2c_device_remove(struct device *dev) device_init_wakeup(&client->dev, false); client->irq = client->init_irq; + if (client->flags & I2C_CLIENT_HOST_NOTIFY) + pm_runtime_put(&client->adapter->dev); return status; } @@ -2258,7 +2262,8 @@ EXPORT_SYMBOL(i2c_put_adapter); /** * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg * @msg: the message to be checked - * @threshold: the minimum number of bytes for which using DMA makes sense + * @threshold: the minimum number of bytes for which using DMA makes sense. + * Should at least be 1. * * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. * Or a valid pointer to be used with DMA. After use, release it by @@ -2268,7 +2273,11 @@ EXPORT_SYMBOL(i2c_put_adapter); */ u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) { - if (msg->len < threshold) + /* also skip 0-length msgs for bogus thresholds of 0 */ + if (!threshold) + pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", + msg->addr); + if (msg->len < threshold || msg->len == 0) return NULL; if (msg->flags & I2C_M_DMA_SAFE) |