From 9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bruno=20Pr=C3=A9mont?= Date: Tue, 30 Mar 2010 22:38:09 +0200 Subject: HID: add experimental access to PicoLCD device's EEPROM and FLASH MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The PicoLCD device has a small amount of EEPROM and also provides access to its FLASH where firmware and splash image are saved. In flasher mode FLASH access is the only active feature. Give read/write access to both via debugfs files. NOTE: EEPROM and FLASH access should be switched to better suited API, until then the will reside in debugfs Signed-off-by: Bruno Prémont Signed-off-by: Jiri Kosina --- drivers/hid/hid-picolcd.c | 439 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 422 insertions(+), 17 deletions(-) (limited to 'drivers/hid/hid-picolcd.c') diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c index 5176773..66f9cfd 100644 --- a/drivers/hid/hid-picolcd.c +++ b/drivers/hid/hid-picolcd.c @@ -169,6 +169,10 @@ struct picolcd_pending { struct picolcd_data { struct hid_device *hdev; #ifdef CONFIG_DEBUG_FS + struct dentry *debug_reset; + struct dentry *debug_eeprom; + struct dentry *debug_flash; + struct mutex mutex_flash; int addr_sz; #endif u8 version[2]; @@ -1314,6 +1318,357 @@ static DEVICE_ATTR(operation_mode, 0644, picolcd_operation_mode_show, #ifdef CONFIG_DEBUG_FS /* + * The "reset" file + */ +static int picolcd_debug_reset_show(struct seq_file *f, void *p) +{ + if (picolcd_fbinfo((struct picolcd_data *)f->private)) + seq_printf(f, "all fb\n"); + else + seq_printf(f, "all\n"); + return 0; +} + +static int picolcd_debug_reset_open(struct inode *inode, struct file *f) +{ + return single_open(f, picolcd_debug_reset_show, inode->i_private); +} + +static ssize_t picolcd_debug_reset_write(struct file *f, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct picolcd_data *data = ((struct seq_file *)f->private_data)->private; + char buf[32]; + size_t cnt = min(count, sizeof(buf)-1); + if (copy_from_user(buf, user_buf, cnt)) + return -EFAULT; + + while (cnt > 0 && (buf[cnt-1] == ' ' || buf[cnt-1] == '\n')) + cnt--; + buf[cnt] = '\0'; + if (strcmp(buf, "all") == 0) { + picolcd_reset(data->hdev); + picolcd_fb_reset(data, 1); + } else if (strcmp(buf, "fb") == 0) { + picolcd_fb_reset(data, 1); + } else { + return -EINVAL; + } + return count; +} + +static const struct file_operations picolcd_debug_reset_fops = { + .owner = THIS_MODULE, + .open = picolcd_debug_reset_open, + .read = seq_read, + .llseek = seq_lseek, + .write = picolcd_debug_reset_write, + .release = single_release, +}; + +/* + * The "eeprom" file + */ +static int picolcd_debug_eeprom_open(struct inode *i, struct file *f) +{ + f->private_data = i->i_private; + return 0; +} + +static ssize_t picolcd_debug_eeprom_read(struct file *f, char __user *u, + size_t s, loff_t *off) +{ + struct picolcd_data *data = f->private_data; + struct picolcd_pending *resp; + u8 raw_data[3]; + ssize_t ret = -EIO; + + if (s == 0) + return -EINVAL; + if (*off > 0x0ff) + return 0; + + /* prepare buffer with info about what we want to read (addr & len) */ + raw_data[0] = *off & 0xff; + raw_data[1] = (*off >> 8) && 0xff; + raw_data[2] = s < 20 ? s : 20; + if (*off + raw_data[2] > 0xff) + raw_data[2] = 0x100 - *off; + resp = picolcd_send_and_wait(data->hdev, REPORT_EE_READ, raw_data, + sizeof(raw_data)); + if (!resp) + return -EIO; + + if (resp->in_report && resp->in_report->id == REPORT_EE_DATA) { + /* successful read :) */ + ret = resp->raw_data[2]; + if (ret > s) + ret = s; + if (copy_to_user(u, resp->raw_data+3, ret)) + ret = -EFAULT; + else + *off += ret; + } /* anything else is some kind of IO error */ + + kfree(resp); + return ret; +} + +static ssize_t picolcd_debug_eeprom_write(struct file *f, const char __user *u, + size_t s, loff_t *off) +{ + struct picolcd_data *data = f->private_data; + struct picolcd_pending *resp; + ssize_t ret = -EIO; + u8 raw_data[23]; + + if (s == 0) + return -EINVAL; + if (*off > 0x0ff) + return -ENOSPC; + + memset(raw_data, 0, sizeof(raw_data)); + raw_data[0] = *off & 0xff; + raw_data[1] = (*off >> 8) && 0xff; + raw_data[2] = s < 20 ? s : 20; + if (*off + raw_data[2] > 0xff) + raw_data[2] = 0x100 - *off; + + if (copy_from_user(raw_data+3, u, raw_data[2])) + return -EFAULT; + resp = picolcd_send_and_wait(data->hdev, REPORT_EE_WRITE, raw_data, + sizeof(raw_data)); + + if (!resp) + return -EIO; + + if (resp->in_report && resp->in_report->id == REPORT_EE_DATA) { + /* check if written data matches */ + if (memcmp(raw_data, resp->raw_data, 3+raw_data[2]) == 0) { + *off += raw_data[2]; + ret = raw_data[2]; + } + } + kfree(resp); + return ret; +} + +/* + * Notes: + * - read/write happens in chunks of at most 20 bytes, it's up to userspace + * to loop in order to get more data. + * - on write errors on otherwise correct write request the bytes + * that should have been written are in undefined state. + */ +static const struct file_operations picolcd_debug_eeprom_fops = { + .owner = THIS_MODULE, + .open = picolcd_debug_eeprom_open, + .read = picolcd_debug_eeprom_read, + .write = picolcd_debug_eeprom_write, + .llseek = generic_file_llseek, +}; + +/* + * The "flash" file + */ +static int picolcd_debug_flash_open(struct inode *i, struct file *f) +{ + f->private_data = i->i_private; + return 0; +} + +/* record a flash address to buf (bounds check to be done by caller) */ +static int _picolcd_flash_setaddr(struct picolcd_data *data, u8 *buf, long off) +{ + buf[0] = off & 0xff; + buf[1] = (off >> 8) & 0xff; + if (data->addr_sz == 3) + buf[2] = (off >> 16) & 0xff; + return data->addr_sz == 2 ? 2 : 3; +} + +/* read a given size of data (bounds check to be done by caller) */ +static ssize_t _picolcd_flash_read(struct picolcd_data *data, int report_id, + char __user *u, size_t s, loff_t *off) +{ + struct picolcd_pending *resp; + u8 raw_data[4]; + ssize_t ret = 0; + int len_off, err = -EIO; + + while (s > 0) { + err = -EIO; + len_off = _picolcd_flash_setaddr(data, raw_data, *off); + raw_data[len_off] = s > 32 ? 32 : s; + resp = picolcd_send_and_wait(data->hdev, report_id, raw_data, len_off+1); + if (!resp || !resp->in_report) + goto skip; + if (resp->in_report->id == REPORT_MEMORY || + resp->in_report->id == REPORT_BL_READ_MEMORY) { + if (memcmp(raw_data, resp->raw_data, len_off+1) != 0) + goto skip; + if (copy_to_user(u+ret, resp->raw_data+len_off+1, raw_data[len_off])) { + err = -EFAULT; + goto skip; + } + *off += raw_data[len_off]; + s -= raw_data[len_off]; + ret += raw_data[len_off]; + err = 0; + } +skip: + kfree(resp); + if (err) + return ret > 0 ? ret : err; + } + return ret; +} + +static ssize_t picolcd_debug_flash_read(struct file *f, char __user *u, + size_t s, loff_t *off) +{ + struct picolcd_data *data = f->private_data; + + if (s == 0) + return -EINVAL; + if (*off > 0x05fff) + return 0; + if (*off + s > 0x05fff) + s = 0x06000 - *off; + + if (data->status & PICOLCD_BOOTLOADER) + return _picolcd_flash_read(data, REPORT_BL_READ_MEMORY, u, s, off); + else + return _picolcd_flash_read(data, REPORT_READ_MEMORY, u, s, off); +} + +/* erase block aligned to 64bytes boundary */ +static ssize_t _picolcd_flash_erase64(struct picolcd_data *data, int report_id, + loff_t *off) +{ + struct picolcd_pending *resp; + u8 raw_data[3]; + int len_off; + ssize_t ret = -EIO; + + if (*off & 0x3f) + return -EINVAL; + + len_off = _picolcd_flash_setaddr(data, raw_data, *off); + resp = picolcd_send_and_wait(data->hdev, report_id, raw_data, len_off); + if (!resp || !resp->in_report) + goto skip; + if (resp->in_report->id == REPORT_MEMORY || + resp->in_report->id == REPORT_BL_ERASE_MEMORY) { + if (memcmp(raw_data, resp->raw_data, len_off) != 0) + goto skip; + ret = 0; + } +skip: + kfree(resp); + return ret; +} + +/* write a given size of data (bounds check to be done by caller) */ +static ssize_t _picolcd_flash_write(struct picolcd_data *data, int report_id, + const char __user *u, size_t s, loff_t *off) +{ + struct picolcd_pending *resp; + u8 raw_data[36]; + ssize_t ret = 0; + int len_off, err = -EIO; + + while (s > 0) { + err = -EIO; + len_off = _picolcd_flash_setaddr(data, raw_data, *off); + raw_data[len_off] = s > 32 ? 32 : s; + if (copy_from_user(raw_data+len_off+1, u, raw_data[len_off])) { + err = -EFAULT; + goto skip; + } + resp = picolcd_send_and_wait(data->hdev, report_id, raw_data, + len_off+1+raw_data[len_off]); + if (!resp || !resp->in_report) + goto skip; + if (resp->in_report->id == REPORT_MEMORY || + resp->in_report->id == REPORT_BL_WRITE_MEMORY) { + if (memcmp(raw_data, resp->raw_data, len_off+1+raw_data[len_off]) != 0) + goto skip; + *off += raw_data[len_off]; + s -= raw_data[len_off]; + ret += raw_data[len_off]; + err = 0; + } +skip: + kfree(resp); + if (err) + break; + } + return ret > 0 ? ret : err; +} + +static ssize_t picolcd_debug_flash_write(struct file *f, const char __user *u, + size_t s, loff_t *off) +{ + struct picolcd_data *data = f->private_data; + ssize_t err, ret = 0; + int report_erase, report_write; + + if (s == 0) + return -EINVAL; + if (*off > 0x5fff) + return -ENOSPC; + if (s & 0x3f) + return -EINVAL; + if (*off & 0x3f) + return -EINVAL; + + if (data->status & PICOLCD_BOOTLOADER) { + report_erase = REPORT_BL_ERASE_MEMORY; + report_write = REPORT_BL_WRITE_MEMORY; + } else { + report_erase = REPORT_ERASE_MEMORY; + report_write = REPORT_WRITE_MEMORY; + } + mutex_lock(&data->mutex_flash); + while (s > 0) { + err = _picolcd_flash_erase64(data, report_erase, off); + if (err) + break; + err = _picolcd_flash_write(data, report_write, u, 64, off); + if (err < 0) + break; + ret += err; + *off += err; + s -= err; + if (err != 64) + break; + } + mutex_unlock(&data->mutex_flash); + return ret > 0 ? ret : err; +} + +/* + * Notes: + * - concurrent writing is prevented by mutex and all writes must be + * n*64 bytes and 64-byte aligned, each write being preceeded by an + * ERASE which erases a 64byte block. + * If less than requested was written or an error is returned for an + * otherwise correct write request the next 64-byte block which should + * have been written is in undefined state (mostly: original, erased, + * (half-)written with write error) + * - reading can happend without special restriction + */ +static const struct file_operations picolcd_debug_flash_fops = { + .owner = THIS_MODULE, + .open = picolcd_debug_flash_open, + .read = picolcd_debug_flash_read, + .write = picolcd_debug_flash_write, + .llseek = generic_file_llseek, +}; + + +/* * Helper code for HID report level dumping/debugging */ static const char *error_codes[] = { @@ -1788,9 +2143,66 @@ static void picolcd_debug_raw_event(struct picolcd_data *data, wake_up_interruptible(&hdev->debug_wait); kfree(buff); } + +static void picolcd_init_devfs(struct picolcd_data *data, + struct hid_report *eeprom_r, struct hid_report *eeprom_w, + struct hid_report *flash_r, struct hid_report *flash_w, + struct hid_report *reset) +{ + struct hid_device *hdev = data->hdev; + + mutex_init(&data->mutex_flash); + + /* reset */ + if (reset) + data->debug_reset = debugfs_create_file("reset", 0600, + hdev->debug_dir, data, &picolcd_debug_reset_fops); + + /* eeprom */ + if (eeprom_r || eeprom_w) + data->debug_eeprom = debugfs_create_file("eeprom", + (eeprom_w ? S_IWUSR : 0) | (eeprom_r ? S_IRUSR : 0), + hdev->debug_dir, data, &picolcd_debug_eeprom_fops); + + /* flash */ + if (flash_r && flash_r->maxfield == 1 && flash_r->field[0]->report_size == 8) + data->addr_sz = flash_r->field[0]->report_count - 1; + else + data->addr_sz = -1; + if (data->addr_sz == 2 || data->addr_sz == 3) { + data->debug_flash = debugfs_create_file("flash", + (flash_w ? S_IWUSR : 0) | (flash_r ? S_IRUSR : 0), + hdev->debug_dir, data, &picolcd_debug_flash_fops); + } else if (flash_r || flash_w) + dev_warn(&hdev->dev, "Unexpected FLASH access reports, " + "please submit rdesc for review\n"); +} + +static void picolcd_exit_devfs(struct picolcd_data *data) +{ + struct dentry *dent; + + dent = data->debug_reset; + data->debug_reset = NULL; + if (dent) + debugfs_remove(dent); + dent = data->debug_eeprom; + data->debug_eeprom = NULL; + if (dent) + debugfs_remove(dent); + dent = data->debug_flash; + data->debug_flash = NULL; + if (dent) + debugfs_remove(dent); + mutex_destroy(&data->mutex_flash); +} #else #define picolcd_debug_raw_event(data, hdev, report, raw_data, size) -#endif +#define picolcd_init_devfs(data, eeprom_r, eeprom_w, flash_r, flash_w, reset) +static void picolcd_exit_devfs(struct picolcd_data *data) +{ +} +#endif /* CONFIG_DEBUG_FS */ /* * Handle raw report as sent by device @@ -1900,7 +2312,6 @@ static inline void picolcd_exit_cir(struct picolcd_data *data) static int picolcd_probe_lcd(struct hid_device *hdev, struct picolcd_data *data) { - struct hid_report *report; int error; error = picolcd_check_version(hdev); @@ -1942,13 +2353,11 @@ static int picolcd_probe_lcd(struct hid_device *hdev, struct picolcd_data *data) if (error) goto err; -#ifdef CONFIG_DEBUG_FS - report = picolcd_out_report(REPORT_READ_MEMORY, hdev); - if (report && report->maxfield == 1 && report->field[0]->report_size == 8) - data->addr_sz = report->field[0]->report_count - 1; - else - data->addr_sz = -1; -#endif + picolcd_init_devfs(data, picolcd_out_report(REPORT_EE_READ, hdev), + picolcd_out_report(REPORT_EE_WRITE, hdev), + picolcd_out_report(REPORT_READ_MEMORY, hdev), + picolcd_out_report(REPORT_WRITE_MEMORY, hdev), + picolcd_out_report(REPORT_RESET, hdev)); return 0; err: picolcd_exit_leds(data); @@ -1962,7 +2371,6 @@ err: static int picolcd_probe_bootloader(struct hid_device *hdev, struct picolcd_data *data) { - struct hid_report *report; int error; error = picolcd_check_version(hdev); @@ -1974,13 +2382,9 @@ static int picolcd_probe_bootloader(struct hid_device *hdev, struct picolcd_data "please submit /sys/kernel/debug/hid/%s/rdesc for this device.\n", dev_name(&hdev->dev)); -#ifdef CONFIG_DEBUG_FS - report = picolcd_out_report(REPORT_BL_READ_MEMORY, hdev); - if (report && report->maxfield == 1 && report->field[0]->report_size == 8) - data->addr_sz = report->field[0]->report_count - 1; - else - data->addr_sz = -1; -#endif + picolcd_init_devfs(data, NULL, NULL, + picolcd_out_report(REPORT_BL_READ_MEMORY, hdev), + picolcd_out_report(REPORT_BL_WRITE_MEMORY, hdev), NULL); return 0; } @@ -2073,6 +2477,7 @@ static void picolcd_remove(struct hid_device *hdev) data->status |= PICOLCD_FAILED; spin_unlock_irqrestore(&data->lock, flags); + picolcd_exit_devfs(data); device_remove_file(&hdev->dev, &dev_attr_operation_mode); hdev->ll_driver->close(hdev); hid_hw_stop(hdev); -- cgit v1.1