From 5bfb7c2ae4275be338d2a1a85904b97835a13ec5 Mon Sep 17 00:00:00 2001 From: "Geoffrey D. Bennett" Date: Wed, 13 Mar 2024 05:04:42 +1030 Subject: [PATCH] ALSA: scarlett2: Add support for reading from flash Add hwdep read op so flash segments can be read. Signed-off-by: Geoffrey D. Bennett Signed-off-by: Takashi Iwai Message-ID: <800d20a801e8c59c2905c82ecae5676cd4f31429.1710264833.git.g@b4.vu> --- sound/usb/mixer_scarlett2.c | 88 +++++++++++++++++++++++++++++++++++-- 1 file changed, 84 insertions(+), 4 deletions(-) diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c index 02c488c80b7e..981ec48a811a 100644 --- a/sound/usb/mixer_scarlett2.c +++ b/sound/usb/mixer_scarlett2.c @@ -1859,6 +1859,7 @@ static int scarlett2_get_port_start_num( #define SCARLETT2_USB_ERASE_SEGMENT 0x00004002 #define SCARLETT2_USB_GET_ERASE 0x00004003 #define SCARLETT2_USB_WRITE_SEGMENT 0x00004004 +#define SCARLETT2_USB_READ_SEGMENT 0x00004005 #define SCARLETT2_USB_GET_SYNC 0x00006004 #define SCARLETT2_USB_GET_DATA 0x00800000 #define SCARLETT2_USB_SET_DATA 0x00800001 @@ -1869,7 +1870,7 @@ static int scarlett2_get_port_start_num( #define SCARLETT2_USB_METER_LEVELS_GET_MAGIC 1 #define SCARLETT2_FLASH_BLOCK_SIZE 4096 -#define SCARLETT2_FLASH_WRITE_MAX 1024 +#define SCARLETT2_FLASH_RW_MAX 1024 #define SCARLETT2_SEGMENT_NUM_MIN 1 #define SCARLETT2_SEGMENT_NUM_MAX 4 @@ -7452,7 +7453,7 @@ static int scarlett2_reboot(struct usb_mixer_interface *mixer) return scarlett2_usb(mixer, SCARLETT2_USB_REBOOT, NULL, 0, NULL, 0); } -/* Select a flash segment for erasing (and possibly writing to) */ +/* Select a flash segment for reading/erasing/writing */ static int scarlett2_ioctl_select_flash_segment( struct usb_mixer_interface *mixer, unsigned long arg) @@ -7633,6 +7634,84 @@ static int scarlett2_hwdep_ioctl(struct snd_hwdep *hw, struct file *file, } } +static long scarlett2_hwdep_read(struct snd_hwdep *hw, + char __user *buf, + long count, loff_t *offset) +{ + struct usb_mixer_interface *mixer = hw->private_data; + struct scarlett2_data *private = mixer->private_data; + int segment_id, segment_num, err; + int flash_size; + + /* SCARLETT2_USB_READ_SEGMENT request data */ + struct { + __le32 segment_num; + __le32 offset; + __le32 len; + } __packed req; + + u8 *resp; + + /* Flash segment must first be selected */ + if (private->flash_write_state != SCARLETT2_FLASH_WRITE_STATE_SELECTED) + return -EINVAL; + + /* Get the selected flash segment number */ + segment_id = private->selected_flash_segment_id; + if (segment_id < 0 || segment_id >= SCARLETT2_SEGMENT_ID_COUNT) + return -EINVAL; + + segment_num = private->flash_segment_nums[segment_id]; + if (segment_num < 0 || + segment_num > SCARLETT2_SEGMENT_NUM_MAX) + return -EFAULT; + + /* Validate the offset and count */ + if (count < 0 || *offset < 0) + return -EINVAL; + + /* Reached EOF? */ + flash_size = private->flash_segment_blocks[segment_id] * + SCARLETT2_FLASH_BLOCK_SIZE; + if (!count || *offset >= flash_size) + return 0; + + /* Limit the numbers of bytes read to SCARLETT2_FLASH_RW_MAX */ + if (count > SCARLETT2_FLASH_RW_MAX) + count = SCARLETT2_FLASH_RW_MAX; + + /* Limit read to EOF */ + if (*offset + count >= flash_size) + count = flash_size - *offset; + + /* Create and send the request */ + req.segment_num = cpu_to_le32(segment_num); + req.offset = cpu_to_le32(*offset); + req.len = cpu_to_le32(count); + + resp = kzalloc(count, GFP_KERNEL); + if (!resp) + return -ENOMEM; + + err = scarlett2_usb(mixer, SCARLETT2_USB_READ_SEGMENT, + &req, sizeof(req), resp, count); + if (err < 0) + goto error; + + /* Copy the response to userspace */ + if (copy_to_user(buf, resp, count)) { + err = -EFAULT; + goto error; + } + + *offset += count; + err = count; + +error: + kfree(resp); + return err; +} + static long scarlett2_hwdep_write(struct snd_hwdep *hw, const char __user *buf, long count, loff_t *offset) @@ -7651,7 +7730,7 @@ static long scarlett2_hwdep_write(struct snd_hwdep *hw, } __packed *req; /* Calculate the maximum permitted in data[] */ - const size_t max_data_size = SCARLETT2_FLASH_WRITE_MAX - + const size_t max_data_size = SCARLETT2_FLASH_RW_MAX - offsetof(typeof(*req), data); /* If erasing, wait for it to complete */ @@ -7688,7 +7767,7 @@ static long scarlett2_hwdep_write(struct snd_hwdep *hw, if (!count) return 0; - /* Limit the *req size to SCARLETT2_FLASH_WRITE_MAX */ + /* Limit the *req size to SCARLETT2_FLASH_RW_MAX */ if (count > max_data_size) count = max_data_size; @@ -7749,6 +7828,7 @@ static int scarlett2_hwdep_init(struct usb_mixer_interface *mixer) hw->exclusive = 1; hw->ops.open = scarlett2_hwdep_open; hw->ops.ioctl = scarlett2_hwdep_ioctl; + hw->ops.read = scarlett2_hwdep_read; hw->ops.write = scarlett2_hwdep_write; hw->ops.release = scarlett2_hwdep_release;