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dmaengine: sirf: add PM entries for sleep and runtime

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this patch adds PM ops entries in sirf-dma drivers, so that this
driver can support suspend/resume, hibernation and runtime PM.

while suspending, sirf-dma will lose all registers, so we save
them at suspend and restore in resume for active channels.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Rongjun Ying <Rongjun.Ying@csr.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Barry Song 2013-07-30 17:44:34 +08:00 committed by Vinod Koul
parent d4adcc0160
commit 2a76689bca
1 changed files with 129 additions and 3 deletions
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132
drivers/dma/sirf-dma.c
View file

@ -9,6 +9,7 @@
#include <linux/module.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/pm_runtime.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/slab.h>
@ -73,6 +74,11 @@ struct sirfsoc_dma_chan {
int mode;
};
struct sirfsoc_dma_regs {
u32 ctrl[SIRFSOC_DMA_CHANNELS];
u32 interrupt_en;
};
struct sirfsoc_dma {
struct dma_device dma;
struct tasklet_struct tasklet;
@ -81,10 +87,13 @@ struct sirfsoc_dma {
int irq;
struct clk *clk;
bool is_marco;
struct sirfsoc_dma_regs regs_save;
};
#define DRV_NAME "sirfsoc_dma"
static int sirfsoc_dma_runtime_suspend(struct device *dev);
/* Convert struct dma_chan to struct sirfsoc_dma_chan */
static inline
struct sirfsoc_dma_chan *dma_chan_to_sirfsoc_dma_chan(struct dma_chan *c)
@ -393,6 +402,8 @@ static int sirfsoc_dma_alloc_chan_resources(struct dma_chan *chan)
LIST_HEAD(descs);
int i;
pm_runtime_get_sync(sdma->dma.dev);
/* Alloc descriptors for this channel */
for (i = 0; i < SIRFSOC_DMA_DESCRIPTORS; i++) {
sdesc = kzalloc(sizeof(*sdesc), GFP_KERNEL);
@ -425,6 +436,7 @@ static int sirfsoc_dma_alloc_chan_resources(struct dma_chan *chan)
static void sirfsoc_dma_free_chan_resources(struct dma_chan *chan)
{
struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
struct sirfsoc_dma_desc *sdesc, *tmp;
unsigned long flags;
LIST_HEAD(descs);
@ -445,6 +457,8 @@ static void sirfsoc_dma_free_chan_resources(struct dma_chan *chan)
/* Free descriptors */
list_for_each_entry_safe(sdesc, tmp, &descs, node)
kfree(sdesc);
pm_runtime_put(sdma->dma.dev);
}
/* Send pending descriptor to hardware */
@ -723,14 +737,14 @@ static int sirfsoc_dma_probe(struct platform_device *op)
tasklet_init(&sdma->tasklet, sirfsoc_dma_tasklet, (unsigned long)sdma);
clk_prepare_enable(sdma->clk);
/* Register DMA engine */
dev_set_drvdata(dev, sdma);
ret = dma_async_device_register(dma);
if (ret)
goto free_irq;
pm_runtime_enable(&op->dev);
dev_info(dev, "initialized SIRFSOC DMAC driver\n");
return 0;
@ -747,13 +761,124 @@ static int sirfsoc_dma_remove(struct platform_device *op)
struct device *dev = &op->dev;
struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
clk_disable_unprepare(sdma->clk);
dma_async_device_unregister(&sdma->dma);
free_irq(sdma->irq, sdma);
irq_dispose_mapping(sdma->irq);
pm_runtime_disable(&op->dev);
if (!pm_runtime_status_suspended(&op->dev))
sirfsoc_dma_runtime_suspend(&op->dev);
return 0;
}
static int sirfsoc_dma_runtime_suspend(struct device *dev)
{
struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
clk_disable_unprepare(sdma->clk);
return 0;
}
static int sirfsoc_dma_runtime_resume(struct device *dev)
{
struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
int ret;
ret = clk_prepare_enable(sdma->clk);
if (ret < 0) {
dev_err(dev, "clk_enable failed: %d\n", ret);
return ret;
}
return 0;
}
static int sirfsoc_dma_pm_suspend(struct device *dev)
{
struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
struct sirfsoc_dma_regs *save = &sdma->regs_save;
struct sirfsoc_dma_desc *sdesc;
struct sirfsoc_dma_chan *schan;
int ch;
int ret;
/*
* if we were runtime-suspended before, resume to enable clock
* before accessing register
*/
if (pm_runtime_status_suspended(dev)) {
ret = sirfsoc_dma_runtime_resume(dev);
if (ret < 0)
return ret;
}
/*
* DMA controller will lose all registers while suspending
* so we need to save registers for active channels
*/
for (ch = 0; ch < SIRFSOC_DMA_CHANNELS; ch++) {
schan = &sdma->channels[ch];
if (list_empty(&schan->active))
continue;
sdesc = list_first_entry(&schan->active,
struct sirfsoc_dma_desc,
node);
save->ctrl[ch] = readl_relaxed(sdma->base +
ch * 0x10 + SIRFSOC_DMA_CH_CTRL);
}
save->interrupt_en = readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN);
/* Disable clock */
sirfsoc_dma_runtime_suspend(dev);
return 0;
}
static int sirfsoc_dma_pm_resume(struct device *dev)
{
struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
struct sirfsoc_dma_regs *save = &sdma->regs_save;
struct sirfsoc_dma_desc *sdesc;
struct sirfsoc_dma_chan *schan;
int ch;
int ret;
/* Enable clock before accessing register */
ret = sirfsoc_dma_runtime_resume(dev);
if (ret < 0)
return ret;
writel_relaxed(save->interrupt_en, sdma->base + SIRFSOC_DMA_INT_EN);
for (ch = 0; ch < SIRFSOC_DMA_CHANNELS; ch++) {
schan = &sdma->channels[ch];
if (list_empty(&schan->active))
continue;
sdesc = list_first_entry(&schan->active,
struct sirfsoc_dma_desc,
node);
writel_relaxed(sdesc->width,
sdma->base + SIRFSOC_DMA_WIDTH_0 + ch * 4);
writel_relaxed(sdesc->xlen,
sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_XLEN);
writel_relaxed(sdesc->ylen,
sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_YLEN);
writel_relaxed(save->ctrl[ch],
sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_CTRL);
writel_relaxed(sdesc->addr >> 2,
sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_ADDR);
}
/* if we were runtime-suspended before, suspend again */
if (pm_runtime_status_suspended(dev))
sirfsoc_dma_runtime_suspend(dev);
return 0;
}
static const struct dev_pm_ops sirfsoc_dma_pm_ops = {
SET_RUNTIME_PM_OPS(sirfsoc_dma_runtime_suspend, sirfsoc_dma_runtime_resume, NULL)
SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_dma_pm_suspend, sirfsoc_dma_pm_resume)
};
static struct of_device_id sirfsoc_dma_match[] = {
{ .compatible = "sirf,prima2-dmac", },
{ .compatible = "sirf,marco-dmac", },
@ -766,6 +891,7 @@ static struct platform_driver sirfsoc_dma_driver = {
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
.pm = &sirfsoc_dma_pm_ops,
.of_match_table = sirfsoc_dma_match,
},
};