[PATCH 5/7] dmaengine: ep93xx: Prepare clock before using it

From: Alexander Sverdlin
Date: Sun Jun 13 2021 - 19:32:44 EST


Use clk_prepare_enable()/clk_disable_unprepare() in preparation for switch
to Common Clock Framework, otherwise the following is visible:

WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:1011 clk_core_enable+0x9c/0xbc
Enabling unprepared m2p0
CPU: 0 PID: 1 Comm: swapper Not tainted 5.13.0-rc5-tekon #1
Hardware name: Cirrus Logic EDB9302 Evaluation Board
[<c000d5b0>] (unwind_backtrace) from [<c000c590>] (show_stack+0x10/0x18)
[<c000c590>] (show_stack) from [<c03a5fb8>] (dump_stack+0x20/0x2c)
[<c03a5fb8>] (dump_stack) from [<c03a2118>] (__warn+0x98/0xc0)
[<c03a2118>] (__warn) from [<c03a21d0>] (warn_slowpath_fmt+0x90/0xc0)
[<c03a21d0>] (warn_slowpath_fmt) from [<c01d8358>] (clk_core_enable+0x9c/0xbc)
[<c01d8358>] (clk_core_enable) from [<c01d8698>] (clk_core_enable_lock+0x18/0x30)
[<c01d8698>] (clk_core_enable_lock) from [<c01e1844>] (ep93xx_dma_alloc_chan_resources+0x94/0x244)
[<c01e1844>] (ep93xx_dma_alloc_chan_resources) from [<c01df7d4>] (dma_chan_get+0x90/0x124)
[<c01df7d4>] (dma_chan_get) from [<c01df92c>] (find_candidate+0xc4/0x188)
[<c01df92c>] (find_candidate) from [<c01dff30>] (__dma_request_channel+0x68/0xb0)
[<c01dff30>] (__dma_request_channel) from [<c027d2e4>] (snd_dmaengine_pcm_request_channel+0x68/0x90)
[<c027d2e4>] (snd_dmaengine_pcm_request_channel) from [<c0290618>] (dmaengine_pcm_new+0x254/0x29c)
[<c0290618>] (dmaengine_pcm_new) from [<c0289b84>] (snd_soc_pcm_component_new+0x40/0xa0)
[<c0289b84>] (snd_soc_pcm_component_new) from [<c028c7f8>] (soc_new_pcm+0x47c/0x5fc)
[<c028c7f8>] (soc_new_pcm) from [<c027f300>] (snd_soc_bind_card+0x73c/0x8a8)
[<c027f300>] (snd_soc_bind_card) from [<c029180c>] (edb93xx_probe+0x34/0x5c)
[<c029180c>] (edb93xx_probe) from [<c02126e0>] (platform_probe+0x34/0x80)
[<c02126e0>] (platform_probe) from [<c0210bf8>] (really_probe+0xe8/0x394)
[<c0210bf8>] (really_probe) from [<c0211464>] (device_driver_attach+0x5c/0x64)
[<c0211464>] (device_driver_attach) from [<c02114e8>] (__driver_attach+0x7c/0xec)
[<c02114e8>] (__driver_attach) from [<c020f1b4>] (bus_for_each_dev+0x78/0xc4)
[<c020f1b4>] (bus_for_each_dev) from [<c0211570>] (driver_attach+0x18/0x24)
[<c0211570>] (driver_attach) from [<c020fab4>] (bus_add_driver+0x140/0x1cc)
[<c020fab4>] (bus_add_driver) from [<c0211c44>] (driver_register+0x74/0x114)
[<c0211c44>] (driver_register) from [<c02134f8>] (__platform_driver_register+0x18/0x24)
[<c02134f8>] (__platform_driver_register) from [<c047084c>] (edb93xx_driver_init+0x10/0x1c)
[<c047084c>] (edb93xx_driver_init) from [<c045ce88>] (do_one_initcall+0x7c/0x1a4)
[<c045ce88>] (do_one_initcall) from [<c045d184>] (kernel_init_freeable+0x17c/0x1fc)
[<c045d184>] (kernel_init_freeable) from [<c03a6550>] (kernel_init+0x8/0xf8)
[<c03a6550>] (kernel_init) from [<c00082d8>] (ret_from_fork+0x14/0x3c)
...
ep93xx-i2s ep93xx-i2s: Missing dma channel for stream: 0
ep93xx-i2s ep93xx-i2s: ASoC: error at snd_soc_pcm_component_new on ep93xx-i2s: -22
edb93xx-audio edb93xx-audio: ASoC: can't create pcm CS4271 HiFi :-22
edb93xx-audio edb93xx-audio: snd_soc_register_card() failed: -22
edb93xx-audio: probe of edb93xx-audio failed with error -22

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
---
drivers/dma/ep93xx_dma.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c
index 01027779beb8..98f9ee70362e 100644
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -897,7 +897,7 @@ static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan)
if (data && data->name)
name = data->name;

- ret = clk_enable(edmac->clk);
+ ret = clk_prepare_enable(edmac->clk);
if (ret)
return ret;

@@ -936,7 +936,7 @@ static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan)
fail_free_irq:
free_irq(edmac->irq, edmac);
fail_clk_disable:
- clk_disable(edmac->clk);
+ clk_disable_unprepare(edmac->clk);

return ret;
}
@@ -969,7 +969,7 @@ static void ep93xx_dma_free_chan_resources(struct dma_chan *chan)
list_for_each_entry_safe(desc, d, &list, node)
kfree(desc);

- clk_disable(edmac->clk);
+ clk_disable_unprepare(edmac->clk);
free_irq(edmac->irq, edmac);
}

--
2.32.0