diff options
Diffstat (limited to 'drivers/i3c/master.c')
| -rw-r--r-- | drivers/i3c/master.c | 78 |
1 files changed, 75 insertions, 3 deletions
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index 2ef898a8fd80..d946db75df70 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -8,6 +8,7 @@ #include <linux/atomic.h> #include <linux/bug.h> #include <linux/device.h> +#include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/export.h> #include <linux/kernel.h> @@ -1728,6 +1729,79 @@ int i3c_master_do_daa(struct i3c_master_controller *master) EXPORT_SYMBOL_GPL(i3c_master_do_daa); /** + * i3c_master_dma_map_single() - Map buffer for single DMA transfer + * @dev: device object of a device doing DMA + * @buf: destination/source buffer for DMA + * @len: length of transfer + * @force_bounce: true, force to use a bounce buffer, + * false, function will auto check is a bounce buffer required + * @dir: DMA direction + * + * Map buffer for a DMA transfer and allocate a bounce buffer if required. + * + * Return: I3C DMA transfer descriptor or NULL in case of error. + */ +struct i3c_dma *i3c_master_dma_map_single(struct device *dev, void *buf, + size_t len, bool force_bounce, enum dma_data_direction dir) +{ + struct i3c_dma *dma_xfer __free(kfree) = NULL; + void *bounce __free(kfree) = NULL; + void *dma_buf = buf; + + dma_xfer = kzalloc(sizeof(*dma_xfer), GFP_KERNEL); + if (!dma_xfer) + return NULL; + + dma_xfer->dev = dev; + dma_xfer->buf = buf; + dma_xfer->dir = dir; + dma_xfer->len = len; + dma_xfer->map_len = len; + + if (is_vmalloc_addr(buf)) + force_bounce = true; + + if (force_bounce) { + dma_xfer->map_len = ALIGN(len, cache_line_size()); + if (dir == DMA_FROM_DEVICE) + bounce = kzalloc(dma_xfer->map_len, GFP_KERNEL); + else + bounce = kmemdup(buf, dma_xfer->map_len, GFP_KERNEL); + if (!bounce) + return NULL; + dma_buf = bounce; + } + + dma_xfer->addr = dma_map_single(dev, dma_buf, dma_xfer->map_len, dir); + if (dma_mapping_error(dev, dma_xfer->addr)) + return NULL; + + dma_xfer->bounce_buf = no_free_ptr(bounce); + return no_free_ptr(dma_xfer); +} +EXPORT_SYMBOL_GPL(i3c_master_dma_map_single); + +/** + * i3c_master_dma_unmap_single() - Unmap buffer after DMA + * @dma_xfer: DMA transfer and mapping descriptor + * + * Unmap buffer and cleanup DMA transfer descriptor. + */ +void i3c_master_dma_unmap_single(struct i3c_dma *dma_xfer) +{ + dma_unmap_single(dma_xfer->dev, dma_xfer->addr, + dma_xfer->map_len, dma_xfer->dir); + if (dma_xfer->bounce_buf) { + if (dma_xfer->dir == DMA_FROM_DEVICE) + memcpy(dma_xfer->buf, dma_xfer->bounce_buf, + dma_xfer->len); + kfree(dma_xfer->bounce_buf); + } + kfree(dma_xfer); +} +EXPORT_SYMBOL_GPL(i3c_master_dma_unmap_single); + +/** * i3c_master_set_info() - set master device information * @master: master used to send frames on the bus * @info: I3C device information @@ -2490,9 +2564,7 @@ static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master) adap->owner = master->dev.parent->driver->owner; adap->algo = &i3c_master_i2c_algo; strscpy(adap->name, dev_name(master->dev.parent), sizeof(adap->name)); - - /* FIXME: Should we allow i3c masters to override these values? */ - adap->timeout = 1000; + adap->timeout = HZ; adap->retries = 3; id = of_alias_get_id(master->dev.of_node, "i2c"); |