This patch creates a connector specific debugfs interface to read any particular DPCD register. The DPCD register address (hex format) is written to 'i915_dpcd_addr' interface and the corresponding value can be read from 'i915_dpcd_val' interface. Example usage: echo 0x70 > i915_dpcd_addr cat i915_dpcd_val DPCD[0x70]:0x1 Signed-off-by: Durgadoss R <durgadoss.r@xxxxxxxxx> --- This patch is based on top of Jani's patch: "add i915 specific connector debugfs file for DPCD" [https://freedesktop.org/patch/43332/] drivers/gpu/drm/i915/i915_debugfs.c | 102 +++++++++++++++++++++++++++++++++++- drivers/gpu/drm/i915/intel_drv.h | 1 + 2 files changed, 102 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 10ca511..9951d84 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -4865,6 +4865,101 @@ static const struct file_operations i915_dpcd_fops = { .release = single_release, }; +static ssize_t i915_dpcd_addr_write(struct file *file, const char __user *ubuf, + size_t len, loff_t *offp) +{ + struct seq_file *m = file->private_data; + struct drm_connector *connector = m->private; + struct intel_dp *intel_dp = + enc_to_intel_dp(&intel_attached_encoder(connector)->base); + unsigned int reg_addr; + char tmp[16]; + int ret; + + if (!intel_dp) + return -EINVAL; + + if (len >= sizeof(tmp)) + return -EINVAL; + + if (copy_from_user(tmp, ubuf, len)) + return -EFAULT; + + tmp[len] = '\0'; + + ret = sscanf(tmp, "%x\n", ®_addr); + if (ret == 0) + return -EINVAL; + + intel_dp->debugfs_dpcd_addr = reg_addr; + + return len; +} + +static int i915_dpcd_addr_show(struct seq_file *m, void *data) +{ + struct drm_connector *connector = m->private; + struct intel_dp *intel_dp = + enc_to_intel_dp(&intel_attached_encoder(connector)->base); + + if (!intel_dp) + return -EINVAL; + + seq_printf(m, "0x%x\n", intel_dp->debugfs_dpcd_addr); + + return 0; +} + +static int i915_dpcd_addr_open(struct inode *inode, struct file *file) +{ + return single_open(file, i915_dpcd_addr_show, inode->i_private); +} + +static const struct file_operations i915_dpcd_addr_fops = { + .owner = THIS_MODULE, + .open = i915_dpcd_addr_open, + .read = seq_read, + .write = i915_dpcd_addr_write, + .llseek = seq_lseek, + .release = single_release, +}; + +static int i915_dpcd_val_show(struct seq_file *m, void *data) +{ + struct drm_connector *connector = m->private; + struct intel_dp *intel_dp = + enc_to_intel_dp(&intel_attached_encoder(connector)->base); + unsigned int addr; + u8 buf[1]; + int ret; + + if (!intel_dp) + return -EINVAL; + + addr = intel_dp->debugfs_dpcd_addr; + ret = drm_dp_dpcd_readb(&intel_dp->aux, addr, buf); + if (ret < 0) { + DRM_ERROR("dpcd read for 0x%x failed:%d\n", addr, ret); + return ret; + } + + seq_printf(m, "DPCD[0x%x]:0x%x\n", addr, buf[0]); + return 0; +} + +static int i915_dpcd_val_open(struct inode *inode, struct file *file) +{ + return single_open(file, i915_dpcd_val_show, inode->i_private); +} + +static const struct file_operations i915_dpcd_val_fops = { + .owner = THIS_MODULE, + .open = i915_dpcd_val_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + /** * i915_debugfs_connector_add - add i915 specific connector debugfs files * @connector: pointer to a registered drm_connector @@ -4883,9 +4978,14 @@ int i915_debugfs_connector_add(struct drm_connector *connector) return -ENODEV; if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort || - connector->connector_type == DRM_MODE_CONNECTOR_eDP) + connector->connector_type == DRM_MODE_CONNECTOR_eDP) { debugfs_create_file("i915_dpcd", S_IRUGO, root, connector, &i915_dpcd_fops); + debugfs_create_file("i915_dpcd_addr", S_IRUGO | S_IWUSR, + root, connector, &i915_dpcd_addr_fops); + debugfs_create_file("i915_dpcd_val", S_IRUGO, root, + connector, &i915_dpcd_val_fops); + } return 0; } diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 4799b11..0594baa 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -642,6 +642,7 @@ struct intel_dp { unsigned long last_power_cycle; unsigned long last_power_on; unsigned long last_backlight_off; + unsigned int debugfs_dpcd_addr; struct notifier_block edp_notifier; -- 1.9.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
