This protects device resources from use after device removal.
There are 3 ways for driver-device unbinding to happen: - The driver module is unloaded causing the driver to be unregistered. This can't happen as long as there are open file handles because a reference is taken on the module. - The device is removed (Device Tree overlay unloading). This can happen at any time. - The driver sysfs unbind file can be used to unbind the driver from the device. This can happen any time.
v2: Since drm_atomic_helper_shutdown() has to be called after drm_dev_unplug() we don't want do block ->disable after unplug.
Signed-off-by: Noralf Trønnes noralf@tronnes.org --- drivers/gpu/drm/tinydrm/hx8357d.c | 9 ++++-- drivers/gpu/drm/tinydrm/ili9225.c | 23 +++++++++++++-- drivers/gpu/drm/tinydrm/ili9341.c | 9 ++++-- drivers/gpu/drm/tinydrm/mi0283qt.c | 9 ++++-- drivers/gpu/drm/tinydrm/mipi-dbi.c | 42 +++++++++++++++++++++++---- drivers/gpu/drm/tinydrm/repaper.c | 46 ++++++++++++++++++++++-------- drivers/gpu/drm/tinydrm/st7586.c | 24 +++++++++++++--- drivers/gpu/drm/tinydrm/st7735r.c | 9 ++++-- 8 files changed, 139 insertions(+), 32 deletions(-)
diff --git a/drivers/gpu/drm/tinydrm/hx8357d.c b/drivers/gpu/drm/tinydrm/hx8357d.c index e9b9e08fafc7..fab961dded87 100644 --- a/drivers/gpu/drm/tinydrm/hx8357d.c +++ b/drivers/gpu/drm/tinydrm/hx8357d.c @@ -50,13 +50,16 @@ static void yx240qv29_enable(struct drm_simple_display_pipe *pipe, { struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev); u8 addr_mode; - int ret; + int ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return;
DRM_DEBUG_KMS("\n");
ret = mipi_dbi_poweron_conditional_reset(mipi); if (ret < 0) - return; + goto out_exit; if (ret == 1) goto out_enable;
@@ -172,6 +175,8 @@ static void yx240qv29_enable(struct drm_simple_display_pipe *pipe, } mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode); mipi_dbi_enable_flush(mipi, crtc_state, plane_state); +out_exit: + drm_dev_exit(idx); }
static const struct drm_simple_display_pipe_funcs hx8357d_pipe_funcs = { diff --git a/drivers/gpu/drm/tinydrm/ili9225.c b/drivers/gpu/drm/tinydrm/ili9225.c index 4d387a07c48b..0e9fde47b53b 100644 --- a/drivers/gpu/drm/tinydrm/ili9225.c +++ b/drivers/gpu/drm/tinydrm/ili9225.c @@ -89,13 +89,16 @@ static void ili9225_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect) bool swap = mipi->swap_bytes; u16 x_start, y_start; u16 x1, x2, y1, y2; - int ret = 0; + int idx, ret = 0; bool full; void *tr;
if (!mipi->enabled) return;
+ if (!drm_dev_enter(fb->dev, &idx)) + return; + full = width == fb->width && height == fb->height;
DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect)); @@ -158,6 +161,8 @@ static void ili9225_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect) err_msg: if (ret) dev_err_once(fb->dev->dev, "Failed to update display %d\n", ret); + + drm_dev_exit(idx); }
static void ili9225_pipe_update(struct drm_simple_display_pipe *pipe, @@ -191,9 +196,12 @@ static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe, .y1 = 0, .y2 = fb->height, }; - int ret; + int ret, idx; u8 am_id;
+ if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + DRM_DEBUG_KMS("\n");
mipi_dbi_hw_reset(mipi); @@ -207,7 +215,7 @@ static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe, ret = ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0000); if (ret) { DRM_DEV_ERROR(dev, "Error sending command %d\n", ret); - return; + goto out_exit; } ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0000); ili9225_command(mipi, ILI9225_POWER_CONTROL_3, 0x0000); @@ -280,6 +288,8 @@ static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe,
mipi->enabled = true; ili9225_fb_dirty(fb, &rect); +out_exit: + drm_dev_exit(idx); }
static void ili9225_pipe_disable(struct drm_simple_display_pipe *pipe) @@ -288,6 +298,13 @@ static void ili9225_pipe_disable(struct drm_simple_display_pipe *pipe)
DRM_DEBUG_KMS("\n");
+ /* + * This callback is not protected by drm_dev_enter/exit since we want to + * turn off the display on regular driver unload. It's highly unlikely + * that the underlying SPI controller is gone should this be called after + * unplug. + */ + if (!mipi->enabled) return;
diff --git a/drivers/gpu/drm/tinydrm/ili9341.c b/drivers/gpu/drm/tinydrm/ili9341.c index 850ce9ed6dd2..d15f85e837ae 100644 --- a/drivers/gpu/drm/tinydrm/ili9341.c +++ b/drivers/gpu/drm/tinydrm/ili9341.c @@ -56,13 +56,16 @@ static void yx240qv29_enable(struct drm_simple_display_pipe *pipe, { struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev); u8 addr_mode; - int ret; + int ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return;
DRM_DEBUG_KMS("\n");
ret = mipi_dbi_poweron_conditional_reset(mipi); if (ret < 0) - return; + goto out_exit; if (ret == 1) goto out_enable;
@@ -128,6 +131,8 @@ static void yx240qv29_enable(struct drm_simple_display_pipe *pipe, addr_mode |= ILI9341_MADCTL_BGR; mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode); mipi_dbi_enable_flush(mipi, crtc_state, plane_state); +out_exit: + drm_dev_exit(idx); }
static const struct drm_simple_display_pipe_funcs ili9341_pipe_funcs = { diff --git a/drivers/gpu/drm/tinydrm/mi0283qt.c b/drivers/gpu/drm/tinydrm/mi0283qt.c index 7aee05586e92..c6dc31084a4e 100644 --- a/drivers/gpu/drm/tinydrm/mi0283qt.c +++ b/drivers/gpu/drm/tinydrm/mi0283qt.c @@ -58,13 +58,16 @@ static void mi0283qt_enable(struct drm_simple_display_pipe *pipe, { struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev); u8 addr_mode; - int ret; + int ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return;
DRM_DEBUG_KMS("\n");
ret = mipi_dbi_poweron_conditional_reset(mipi); if (ret < 0) - return; + goto out_exit; if (ret == 1) goto out_enable;
@@ -136,6 +139,8 @@ static void mi0283qt_enable(struct drm_simple_display_pipe *pipe, addr_mode |= ILI9341_MADCTL_BGR; mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode); mipi_dbi_enable_flush(mipi, crtc_state, plane_state); +out_exit: + drm_dev_exit(idx); }
static const struct drm_simple_display_pipe_funcs mi0283qt_pipe_funcs = { diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c b/drivers/gpu/drm/tinydrm/mipi-dbi.c index 5c848f975ebe..34d544f6e52d 100644 --- a/drivers/gpu/drm/tinydrm/mipi-dbi.c +++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c @@ -220,13 +220,16 @@ static void mipi_dbi_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect) unsigned int height = rect->y2 - rect->y1; unsigned int width = rect->x2 - rect->x1; bool swap = mipi->swap_bytes; - int ret = 0; + int idx, ret = 0; bool full; void *tr;
if (!mipi->enabled) return;
+ if (!drm_dev_enter(fb->dev, &idx)) + return; + full = width == fb->width && height == fb->height;
DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect)); @@ -253,6 +256,8 @@ static void mipi_dbi_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect) err_msg: if (ret) dev_err_once(fb->dev->dev, "Failed to update display %d\n", ret); + + drm_dev_exit(idx); }
/** @@ -307,10 +312,16 @@ void mipi_dbi_enable_flush(struct mipi_dbi *mipi, .y1 = 0, .y2 = fb->height, }; + int idx; + + if (!drm_dev_enter(&mipi->drm, &idx)) + return;
mipi->enabled = true; mipi_dbi_fb_dirty(fb, &rect); backlight_enable(mipi->backlight); + + drm_dev_exit(idx); } EXPORT_SYMBOL(mipi_dbi_enable_flush);
@@ -320,6 +331,10 @@ static void mipi_dbi_blank(struct mipi_dbi *mipi) u16 height = drm->mode_config.min_height; u16 width = drm->mode_config.min_width; size_t len = width * height * 2; + int idx; + + if (!drm_dev_enter(drm, &idx)) + return;
memset(mipi->tx_buf, 0, len);
@@ -329,6 +344,8 @@ static void mipi_dbi_blank(struct mipi_dbi *mipi) (height >> 8) & 0xFF, (height - 1) & 0xFF); mipi_dbi_command_buf(mipi, MIPI_DCS_WRITE_MEMORY_START, (u8 *)mipi->tx_buf, len); + + drm_dev_exit(idx); }
/** @@ -343,6 +360,9 @@ void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe) { struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev);
+ if (!mipi->enabled) + return; + DRM_DEBUG_KMS("\n");
mipi->enabled = false; @@ -991,11 +1011,16 @@ static ssize_t mipi_dbi_debugfs_command_write(struct file *file, u8 val, cmd = 0, parameters[64]; char *buf, *pos, *token; unsigned int i; - int ret; + int ret, idx; + + if (!drm_dev_enter(&mipi->drm, &idx)) + return -ENODEV;
buf = memdup_user_nul(ubuf, count); - if (IS_ERR(buf)) - return PTR_ERR(buf); + if (IS_ERR(buf)) { + ret = PTR_ERR(buf); + goto err_exit; + }
/* strip trailing whitespace */ for (i = count - 1; i > 0; i--) @@ -1031,6 +1056,8 @@ static ssize_t mipi_dbi_debugfs_command_write(struct file *file,
err_free: kfree(buf); +err_exit: + drm_dev_exit(idx);
return ret < 0 ? ret : count; } @@ -1039,8 +1066,11 @@ static int mipi_dbi_debugfs_command_show(struct seq_file *m, void *unused) { struct mipi_dbi *mipi = m->private; u8 cmd, val[4]; + int ret, idx; size_t len; - int ret; + + if (!drm_dev_enter(&mipi->drm, &idx)) + return -ENODEV;
for (cmd = 0; cmd < 255; cmd++) { if (!mipi_dbi_command_is_read(mipi, cmd)) @@ -1071,6 +1101,8 @@ static int mipi_dbi_debugfs_command_show(struct seq_file *m, void *unused) seq_printf(m, "%*phN\n", (int)len, val); }
+ drm_dev_exit(idx); + return 0; }
diff --git a/drivers/gpu/drm/tinydrm/repaper.c b/drivers/gpu/drm/tinydrm/repaper.c index b1acf5aebe32..3f3632457079 100644 --- a/drivers/gpu/drm/tinydrm/repaper.c +++ b/drivers/gpu/drm/tinydrm/repaper.c @@ -533,8 +533,14 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb) struct dma_buf_attachment *import_attach = cma_obj->base.import_attach; struct repaper_epd *epd = drm_to_epd(fb->dev); struct drm_rect clip; + int idx, ret = 0; u8 *buf = NULL; - int ret = 0; + + if (!epd->enabled) + return 0; + + if (!drm_dev_enter(fb->dev, &idx)) + return -ENODEV;
/* repaper can't do partial updates */ clip.x1 = 0; @@ -542,17 +548,16 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb) clip.y1 = 0; clip.y2 = fb->height;
- if (!epd->enabled) - return 0; - repaper_get_temperature(epd);
DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id, epd->factored_stage_time);
buf = kmalloc_array(fb->width, fb->height, GFP_KERNEL); - if (!buf) - return -ENOMEM; + if (!buf) { + ret = -ENOMEM; + goto out_exit; + }
if (import_attach) { ret = dma_buf_begin_cpu_access(import_attach->dmabuf, @@ -621,6 +626,8 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb)
out_free: kfree(buf); +out_exit: + drm_dev_exit(idx);
return ret; } @@ -650,7 +657,10 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, struct spi_device *spi = epd->spi; struct device *dev = &spi->dev; bool dc_ok = false; - int i, ret; + int i, ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return;
DRM_DEBUG_DRIVER("\n");
@@ -689,7 +699,7 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, if (!i) { DRM_DEV_ERROR(dev, "timeout waiting for panel to become ready.\n"); power_off(epd); - return; + goto out_exit; }
repaper_read_id(spi); @@ -700,7 +710,7 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, else dev_err(dev, "wrong COG ID 0x%02x\n", ret); power_off(epd); - return; + goto out_exit; }
/* Disable OE */ @@ -713,7 +723,7 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, else DRM_DEV_ERROR(dev, "panel is reported broken\n"); power_off(epd); - return; + goto out_exit; }
/* Power saving mode */ @@ -753,7 +763,7 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, if (ret < 0) { DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret); power_off(epd); - return; + goto out_exit; }
if (ret & 0x40) { @@ -765,7 +775,7 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, if (!dc_ok) { DRM_DEV_ERROR(dev, "dc/dc failed\n"); power_off(epd); - return; + goto out_exit; }
/* @@ -776,6 +786,8 @@ static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe,
epd->enabled = true; epd->partial = false; +out_exit: + drm_dev_exit(idx); }
static void repaper_pipe_disable(struct drm_simple_display_pipe *pipe) @@ -784,6 +796,16 @@ static void repaper_pipe_disable(struct drm_simple_display_pipe *pipe) struct spi_device *spi = epd->spi; unsigned int line;
+ /* + * This callback is not protected by drm_dev_enter/exit since we want to + * turn off the display on regular driver unload. It's highly unlikely + * that the underlying SPI controller is gone should this be called after + * unplug. + */ + + if (!epd->enabled) + return; + DRM_DEBUG_DRIVER("\n");
epd->enabled = false; diff --git a/drivers/gpu/drm/tinydrm/st7586.c b/drivers/gpu/drm/tinydrm/st7586.c index 6e92de809b63..d99957bac532 100644 --- a/drivers/gpu/drm/tinydrm/st7586.c +++ b/drivers/gpu/drm/tinydrm/st7586.c @@ -119,12 +119,14 @@ static int st7586_buf_copy(void *dst, struct drm_framebuffer *fb, static void st7586_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect) { struct mipi_dbi *mipi = drm_to_mipi_dbi(fb->dev); - int start, end; - int ret = 0; + int start, end, idx, ret = 0;
if (!mipi->enabled) return;
+ if (!drm_dev_enter(fb->dev, &idx)) + return; + /* 3 pixels per byte, so grow clip to nearest multiple of 3 */ rect->x1 = rounddown(rect->x1, 3); rect->x2 = roundup(rect->x2, 3); @@ -152,6 +154,8 @@ static void st7586_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect) err_msg: if (ret) dev_err_once(fb->dev->dev, "Failed to update display %d\n", ret); + + drm_dev_exit(idx); }
static void st7586_pipe_update(struct drm_simple_display_pipe *pipe, @@ -184,14 +188,17 @@ static void st7586_pipe_enable(struct drm_simple_display_pipe *pipe, .y1 = 0, .y2 = fb->height, }; - int ret; + int idx, ret; u8 addr_mode;
+ if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + DRM_DEBUG_KMS("\n");
ret = mipi_dbi_poweron_reset(mipi); if (ret) - return; + goto out_exit;
mipi_dbi_command(mipi, ST7586_AUTO_READ_CTRL, 0x9f); mipi_dbi_command(mipi, ST7586_OTP_RW_CTRL, 0x00); @@ -244,12 +251,21 @@ static void st7586_pipe_enable(struct drm_simple_display_pipe *pipe, st7586_fb_dirty(fb, &rect);
mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON); +out_exit: + drm_dev_exit(idx); }
static void st7586_pipe_disable(struct drm_simple_display_pipe *pipe) { struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev);
+ /* + * This callback is not protected by drm_dev_enter/exit since we want to + * turn off the display on regular driver unload. It's highly unlikely + * that the underlying SPI controller is gone should this be called after + * unplug. + */ + DRM_DEBUG_KMS("\n");
if (!mipi->enabled) diff --git a/drivers/gpu/drm/tinydrm/st7735r.c b/drivers/gpu/drm/tinydrm/st7735r.c index 0f8a346026ac..022e9849b95b 100644 --- a/drivers/gpu/drm/tinydrm/st7735r.c +++ b/drivers/gpu/drm/tinydrm/st7735r.c @@ -44,14 +44,17 @@ static void jd_t18003_t01_pipe_enable(struct drm_simple_display_pipe *pipe, struct drm_plane_state *plane_state) { struct mipi_dbi *mipi = drm_to_mipi_dbi(pipe->crtc.dev); - int ret; + int ret, idx; u8 addr_mode;
+ if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + DRM_DEBUG_KMS("\n");
ret = mipi_dbi_poweron_reset(mipi); if (ret) - return; + goto out_exit;
msleep(150);
@@ -102,6 +105,8 @@ static void jd_t18003_t01_pipe_enable(struct drm_simple_display_pipe *pipe, msleep(20);
mipi_dbi_enable_flush(mipi, crtc_state, plane_state); +out_exit: + drm_dev_exit(idx); }
static const struct drm_simple_display_pipe_funcs jd_t18003_t01_pipe_funcs = {