From bb0a896e3d50833a43f94264ec8e66900b796b8b Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Fri, 30 Dec 2011 14:13:41 -0300 Subject: [PATCH] [media] marvell-cam: Make suspend/resume work on MMP2 Somehow I didn't ever quite get around to implementing suspend/resume on the MMP2 platform; this patch fixes that little oversight. A bit of core work was necessary to do the right thing in the s/g DMA case. Signed-off-by: Jonathan Corbet Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/marvell-ccic/mcam-core.c | 36 +++++++++++++++++++++------ drivers/media/video/marvell-ccic/mmp-driver.c | 35 ++++++++++++++++++++++++++ 2 files changed, 64 insertions(+), 7 deletions(-) diff --git a/drivers/media/video/marvell-ccic/mcam-core.c b/drivers/media/video/marvell-ccic/mcam-core.c index 80ec64d..c1f12f9 100644 --- a/drivers/media/video/marvell-ccic/mcam-core.c +++ b/drivers/media/video/marvell-ccic/mcam-core.c @@ -522,6 +522,15 @@ static void mcam_sg_next_buffer(struct mcam_camera *cam) */ static void mcam_ctlr_dma_sg(struct mcam_camera *cam) { + /* + * The list-empty condition can hit us at resume time + * if the buffer list was empty when the system was suspended. + */ + if (list_empty(&cam->buffers)) { + set_bit(CF_SG_RESTART, &cam->flags); + return; + } + mcam_reg_clear_bit(cam, REG_CTRL1, C1_DESC_3WORD); mcam_sg_next_buffer(cam); mcam_reg_set_bit(cam, REG_CTRL1, C1_DESC_ENA); @@ -566,6 +575,7 @@ static void mcam_dma_sg_done(struct mcam_camera *cam, int frame) } else { set_bit(CF_SG_RESTART, &cam->flags); singles++; + cam->vb_bufs[0] = NULL; } /* * Now we can give the completed frame back to user space. @@ -661,10 +671,10 @@ static int mcam_ctlr_configure(struct mcam_camera *cam) unsigned long flags; spin_lock_irqsave(&cam->dev_lock, flags); + clear_bit(CF_SG_RESTART, &cam->flags); cam->dma_setup(cam); mcam_ctlr_image(cam); mcam_set_config_needed(cam, 0); - clear_bit(CF_SG_RESTART, &cam->flags); spin_unlock_irqrestore(&cam->dev_lock, flags); return 0; } @@ -873,7 +883,8 @@ static int mcam_read_setup(struct mcam_camera *cam) mcam_reset_buffers(cam); mcam_ctlr_irq_enable(cam); cam->state = S_STREAMING; - mcam_ctlr_start(cam); + if (!test_bit(CF_SG_RESTART, &cam->flags)) + mcam_ctlr_start(cam); spin_unlock_irqrestore(&cam->dev_lock, flags); return 0; } @@ -1818,11 +1829,15 @@ void mccic_shutdown(struct mcam_camera *cam) void mccic_suspend(struct mcam_camera *cam) { - enum mcam_state cstate = cam->state; + mutex_lock(&cam->s_mutex); + if (cam->users > 0) { + enum mcam_state cstate = cam->state; - mcam_ctlr_stop_dma(cam); - mcam_ctlr_power_down(cam); - cam->state = cstate; + mcam_ctlr_stop_dma(cam); + mcam_ctlr_power_down(cam); + cam->state = cstate; + } + mutex_unlock(&cam->s_mutex); } int mccic_resume(struct mcam_camera *cam) @@ -1839,8 +1854,15 @@ int mccic_resume(struct mcam_camera *cam) mutex_unlock(&cam->s_mutex); set_bit(CF_CONFIG_NEEDED, &cam->flags); - if (cam->state == S_STREAMING) + if (cam->state == S_STREAMING) { + /* + * If there was a buffer in the DMA engine at suspend + * time, put it back on the queue or we'll forget about it. + */ + if (cam->buffer_mode == B_DMA_sg && cam->vb_bufs[0]) + list_add(&cam->vb_bufs[0]->queue, &cam->buffers); ret = mcam_read_setup(cam); + } return ret; } #endif /* CONFIG_PM */ diff --git a/drivers/media/video/marvell-ccic/mmp-driver.c b/drivers/media/video/marvell-ccic/mmp-driver.c index fb0b124..0d64e2d 100644 --- a/drivers/media/video/marvell-ccic/mmp-driver.c +++ b/drivers/media/video/marvell-ccic/mmp-driver.c @@ -26,6 +26,7 @@ #include #include #include +#include #include "mcam-core.h" @@ -310,10 +311,44 @@ static int mmpcam_platform_remove(struct platform_device *pdev) return mmpcam_remove(cam); } +/* + * Suspend/resume support. + */ +#ifdef CONFIG_PM + +static int mmpcam_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct mmp_camera *cam = mmpcam_find_device(pdev); + + if (state.event != PM_EVENT_SUSPEND) + return 0; + mccic_suspend(&cam->mcam); + return 0; +} + +static int mmpcam_resume(struct platform_device *pdev) +{ + struct mmp_camera *cam = mmpcam_find_device(pdev); + + /* + * Power up unconditionally just in case the core tries to + * touch a register even if nothing was active before; trust + * me, it's better this way. + */ + mmpcam_power_up(&cam->mcam); + return mccic_resume(&cam->mcam); +} + +#endif + static struct platform_driver mmpcam_driver = { .probe = mmpcam_probe, .remove = mmpcam_platform_remove, +#ifdef CONFIG_PM + .suspend = mmpcam_suspend, + .resume = mmpcam_resume, +#endif .driver = { .name = "mmp-camera", .owner = THIS_MODULE -- 2.7.4