Move dma channel allocations to pcmops open and close functions. Reason to do this is that, lpass_platform_pcm_free() accesses snd_soc_pcm_runtime via substream->private data, However By this time runtimes are already freed as part of soc_cleanup_card_resources() sequence.

This patch moves the channel allocations/deallocations to pcmops open() and close() respectively, where the code has valid snd_soc_pcm_runtime.

Without this patch unloading lpass sound card module would result in below crash:

Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ffff800038f0d000 [00000000] *pgd=0000000000000000 Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: snd_soc_apq8016_sbc(-) snd_soc_lpass_apq8016 snd_soc_lpass_cpu snd_soc_lpass_platform CPU: 0 PID: 1573 Comm: rmmod Not tainted 4.7.0-rc2-next-20160609+ #59 Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) task: ffff800038cd0000 ti: ffff80003929c000 task.ti: ffff80003929c000 PC is at lpass_platform_pcm_free+0xc4/0x1c0 [snd_soc_lpass_platform] LR is at lpass_platform_pcm_free+0xb8/0x1c0 [snd_soc_lpass_platform] pc : [<ffff000000b20b64>] lr : [<ffff000000b20b58>] pstate: 60000145 sp : ffff80003929fa90 x29: ffff80003929fa90 x28: ffff000000b22438 x27: ffff000000b22450 x26: ffff000000b22468 x25: ffff000000b22488 x24: ffff000000b223f0 x23: ffff000000b22418 x22: ffff800038f428c0 x21: ffff8000392ae280 x20: 0000000000000001 x19: ffff000000b22118 x18: 0000ffffdc331600 x17: 0000ffffb78036c0 x16: ffff0000081c16e8 x15: 0000ffffb77f0588 x14: 3d4d554e51455300 x13: ffffffffffff0000 x12: 0000000000000028 x11: 0000000000000044 x10: ffff80003929f822 x9 : ffff80003929f823 x8 : 0000000000000000 x7 : 0000000000000004 x6 : ffff000008864890 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : ffff80003efac228 x1 : ffff000000b22118 x0 : ffff000000b22450

Process rmmod (pid: 1573, stack limit = 0xffff80003929c020) Stack: (0xffff80003929fa90 to 0xffff8000392a0000) fa80: ffff80003929fb40 ffff0000086d1f8c faa0: ffff000008ca5408 ffff800038f42200 ffff000008ca5420 000000000000000b fac0: ffff80003929fd70 0000000000000015 0000000000000120 000000000000006a fae0: ffff0000087f2000 ffff80003929c000 ffff80003929fb40 ffff8000392ae358 fb00: ffff8000392af900 0000000000000000 ffff8000392afa48 000000000000000b fb20: ffff80003929fd70 0000000000000015 ffff80003929fb80 ffff0000086cc070 fb40: ffff80003929fb70 ffff0000086d21d4 ffff800038f7fa00 ffff8000392801a0 fb60: ffff800038cf2000 0000000000000015 ffff80003929fb80 ffff0000086cc064 fb80: ffff80003929fba0 ffff0000086cc1f4 ffff800038f70600 000000000000000b fba0: ffff80003929fbc0 ffff0000086c68a8 ffff800039280000 ffff800039280540 fbc0: ffff80003929fbe0 ffff0000084a7438 ffff800039280540 ffff800039280550 fbe0: ffff80003929fc10 ffff000008355ddc ffff800039280550 ffff000008c64718 fc00: ffff800038f61d00 ffff000008ca5190 ffff80003929fc40 ffff000008355e5c fc20: ffff800039280550 ffff800039280000 ffff80003847b618 ffff800039280000 fc40: ffff80003929fc60 ffff0000084a77d8 0000000000000000 0000000000000015 fc60: ffff80003929fc70 ffff0000086c6e58 ffff80003929fc90 ffff0000086c6fbc fc80: ffff80003929fcb0 ffff800039280000 ffff80003929fcd0 ffff0000086e3e50 fca0: ffff80003847b050 ffff80003847b728 ffff800000000000 ffff000000000000 fcc0: ffff80003929fcc0 ffff80003929fcc0 ffff80003929fd00 ffff0000086e4c8c fce0: ffff80003847b618 ffff800038f61100 ffff8000399ddf90 000000000000000b fd00: ffff80003929fd20 ffff0000086f0684 ffff800038f61000 ffff0000080d51c0 fd20: ffff80003929fd30 ffff0000084af904 ffff80003929fd80 ffff0000084afcf8 fd40: ffff8000399ddf90 ffff000000b3c028 ffff8000399ddff0 ffff000008cc8000 fd60: 0000000080000000 ffff0000084ac090 ffff800038f94600 ffff800038f61000 fd80: ffff80003929fda0 ffff0000084ac0b0 ffff8000399ddf90 ffff000000b3c028 fda0: ffff80003929fdc0 ffff0000084ac234 ffff8000399ddf90 ffff000000b3c028 fdc0: ffff80003929fdf0 ffff0000084ab3d4 ffff000000b3c028 ffff000008c64000 fde0: ffff000008c64818 ffff000000000001 ffff80003929fe20 ffff0000084ac8ac fe00: ffff000000b3c028 ffff000000b3c100 fffffffffffffff5 0000000000000000 fe20: ffff80003929fe40 ffff0000084ad998 ffff000008c2d000 0000000000000015 fe40: ffff80003929fe50 ffff000000b3a460 ffff80003929fe60 ffff000008120fe4 fe60: 0000000000000000 ffff000008084e70 0000000000000000 0000000000000000 fe80: ffffffffffffffff 0000ffff954cca48 0000000000000004 5f636f735f646e73 fea0: 5f36313038717061 0000000000636273 0000000000000000 ffff000008084d64 fec0: 0000000000000000 0000000000000000 0000aaaabc814340 0000000000000800 fee0: 4fdc43dac03e2300 0000000000002002 0000ffff95548e58 0000ffffd9f89fb9 ff00: 0000000000000000 0000000000000000 000000000000006a 1999999999999999 ff20: 00000000ffffffff 0000000000000000 0000000000000005 ffffffffffffffff ff40: 0000ffff95402a94 0000ffff9554a588 0000ffff954cca40 0000aaaaaf8d22d0 ff60: 0000ffffd9f8ad70 0000aaaabc8142e0 0000000000000000 0000000000000000 ff80: 0000ffffd9f8be7c 0000000000000000 0000ffffd9f8b0e0 0000ffffd9f8b2b8 ffa0: 0000aaaabc8142e0 0000aaaabc813010 0000000000000000 0000ffffd9f8b010 ffc0: 0000aaaaaf8b5ad4 0000ffffd9f8b010 0000ffff954cca48 0000000080000000 ffe0: 0000aaaabc814340 000000000000006a 0000060000000000 00000000fffefcaf Call trace: Exception stack(0xffff80003929f8d0 to 0xffff80003929f9f0) f8c0: ffff000000b22118 00000000000001 f8e0: ffff80003929fa90 ffff000000b20b64 ffff80003929f910 ffff000008a12f40 f900: ffff000008c15b78 0000000100000001 ffff80003929f9b0 ffff0000080f66e0 f920: ffff000000b22118 0000000000000001 ffff8000392ae280 ffff800038f428c0 f940: ffff000000b22418 ffff000000b223f0 ffff000000b22488 ffff000000b22468 f960: ffff000000b22450 ffff000000b22438 ffff000000b22450 ffff000000b22118 f980: ffff80003efac228 0000000000000000 0000000000000000 0000000000000000 f9a0: ffff000008864890 0000000000000004 0000000000000000 ffff80003929f823 f9c0: ffff80003929f822 0000000000000044 0000000000000028 ffffffffffff0000 f9e0: 3d4d554e51455300 0000ffffb77f0588 [<ffff000000b20b64>] lpass_platform_pcm_free+0xc4/0x1c0 [snd_soc_lpass_platform] [<ffff0000086d1f8c>] snd_pcm_free+0x30/0xa0 [<ffff0000086d21d4>] snd_pcm_dev_free+0x10/0x18 [<ffff0000086cc064>] __snd_device_free+0x58/0xa0 [<ffff0000086cc1f4>] snd_device_free_all+0x2c/0x48 [<ffff0000086c68a8>] release_card_device+0x1c/0x74 [<ffff0000084a7438>] device_release+0x34/0x90 [<ffff000008355ddc>] kobject_release+0x44/0x84 [<ffff000008355e5c>] kobject_put+0x40/0x68 [<ffff0000084a77d8>] put_device+0x14/0x1c [<ffff0000086c6e58>] snd_card_free_when_closed+0x24/0x34 [<ffff0000086c6fbc>] snd_card_free+0x40/0x60 [<ffff0000086e3e50>] soc_cleanup_card_resources+0x80/0x94 [<ffff0000086e4c8c>] snd_soc_unregister_card+0x28/0x38 [<ffff0000086f0684>] devm_card_release+0x10/0x18 [<ffff0000084af904>] release_nodes+0x124/0x208 [<ffff0000084afcf8>] devres_release_all+0x34/0x54 [<ffff0000084ac0b0>] __device_release_driver+0x84/0xfc [<ffff0000084ac234>] driver_detach+0xbc/0xc0 [<ffff0000084ab3d4>] bus_remove_driver+0x58/0xac [<ffff0000084ac8ac>] driver_unregister+0x2c/0x4c [<ffff0000084ad998>] platform_driver_unregister+0x10/0x18 [<ffff000000b3a460>] apq8016_sbc_platform_driver_exit+0x10/0xbb0 [snd_soc_apq8016_sbc] [<ffff000008120fe4>] SyS_delete_module+0x1b8/0x1fc [<ffff000008084e70>] el0_svc_naked+0x24/0x28 Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org --- sound/soc/qcom/lpass-platform.c | 158 ++++++++++++++++++++-------------------- 1 file changed, 77 insertions(+), 81 deletions(-)

diff --git a/sound/soc/qcom/lpass-platform.c b/sound/soc/qcom/lpass-platform.c index db000c6..9987e12 100644 --- a/sound/soc/qcom/lpass-platform.c +++ b/sound/soc/qcom/lpass-platform.c @@ -61,7 +61,36 @@ static int lpass_platform_pcmops_open(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; struct snd_soc_pcm_runtime *soc_runtime = substream->private_data; - int ret; + struct lpass_pcm_data *pcm_data = snd_soc_pcm_get_drvdata(soc_runtime); + struct lpass_data *drvdata = + snd_soc_platform_get_drvdata(soc_runtime->platform); + struct lpass_variant *v = drvdata->variant; + int ch = -1, reg, ret; + + if (v->alloc_dma_channel) { + ch = v->alloc_dma_channel(drvdata, substream->stream); + + if (ch < 0) + return ch; + + drvdata->substream[ch] = substream; + + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { + pcm_data->rdma_ch = ch; + reg = LPAIF_RDMACTL_REG(v, ch); + } else { + pcm_data->wrdma_ch = ch; + reg = LPAIF_WRDMACTL_REG(v, ch); + } + + ret = regmap_write(drvdata->lpaif_map, reg, 0); + if (ret) { + dev_err(soc_runtime->dev, + "%s() error writing to dmactl reg: %d\n", + __func__, ret); + goto err; + } + }

snd_soc_set_runtime_hwparams(substream, &lpass_platform_pcm_hardware);

@@ -72,12 +101,43 @@ static int lpass_platform_pcmops_open(struct snd_pcm_substream *substream) if (ret < 0) { dev_err(soc_runtime->dev, "%s() setting constraints failed: %d\n", __func__, ret); - return -EINVAL; + goto err; }

snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);

return 0; + +err: + if (ch >= 0 && v->free_dma_channel) + v->free_dma_channel(drvdata, ch); + + return ret; +} + +static int lpass_platform_pcmops_close(struct snd_pcm_substream *substream) +{ + struct snd_soc_pcm_runtime *soc_runtime = substream->private_data; + struct lpass_pcm_data *pcm_data = snd_soc_pcm_get_drvdata(soc_runtime); + struct lpass_data *drvdata = + snd_soc_platform_get_drvdata(soc_runtime->platform); + struct lpass_variant *v = drvdata->variant; + int ch = -1; + + if (v->free_dma_channel) { + drvdata->substream[ch] = substream; + + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + ch = pcm_data->rdma_ch; + else + ch = pcm_data->wrdma_ch; + + if (ch >= 0) + v->free_dma_channel(drvdata, ch); + + } + + return 0; }

static int lpass_platform_pcmops_hw_params(struct snd_pcm_substream *substream, @@ -374,6 +434,7 @@ static int lpass_platform_pcmops_mmap(struct snd_pcm_substream *substream,

static struct snd_pcm_ops lpass_platform_pcm_ops = { .open = lpass_platform_pcmops_open, + .close = lpass_platform_pcmops_close, .ioctl = snd_pcm_lib_ioctl, .hw_params = lpass_platform_pcmops_hw_params, .hw_free = lpass_platform_pcmops_hw_free, @@ -471,14 +532,12 @@ static int lpass_platform_pcm_new(struct snd_soc_pcm_runtime *soc_runtime) struct snd_pcm *pcm = soc_runtime->pcm; struct snd_pcm_substream *psubstream, *csubstream; struct snd_soc_dai *cpu_dai = soc_runtime->cpu_dai; - struct lpass_data *drvdata = - snd_soc_platform_get_drvdata(soc_runtime->platform); - struct lpass_variant *v = drvdata->variant; - int ret = -EINVAL; + struct device *dev = soc_runtime->platform->dev; struct lpass_pcm_data *data; size_t size = lpass_platform_pcm_hardware.buffer_bytes_max; + int ret = -EINVAL;

- data = devm_kzalloc(soc_runtime->dev, sizeof(*data), GFP_KERNEL); + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM;

@@ -487,100 +546,37 @@ static int lpass_platform_pcm_new(struct snd_soc_pcm_runtime *soc_runtime)

psubstream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; if (psubstream) { - if (v->alloc_dma_channel) - data->rdma_ch = v->alloc_dma_channel(drvdata, - SNDRV_PCM_STREAM_PLAYBACK); - - if (data->rdma_ch < 0) - return data->rdma_ch; - - drvdata->substream[data->rdma_ch] = psubstream; - - ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, - soc_runtime->platform->dev, - size, &psubstream->dma_buffer); - if (ret) - goto playback_alloc_err; - - ret = regmap_write(drvdata->lpaif_map, - LPAIF_RDMACTL_REG(v, data->rdma_ch), 0); + ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, dev, size, + &psubstream->dma_buffer); if (ret) { - dev_err(soc_runtime->dev, - "%s() error writing to rdmactl reg: %d\n", - __func__, ret); - goto capture_alloc_err; + dev_err(dev, "can't alloc playback dma buffer\n"); + return ret; } }

csubstream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; if (csubstream) { - if (v->alloc_dma_channel) - data->wrdma_ch = v->alloc_dma_channel(drvdata, - SNDRV_PCM_STREAM_CAPTURE); - - if (data->wrdma_ch < 0) { - ret = data->wrdma_ch; - goto capture_alloc_err; - } - - drvdata->substream[data->wrdma_ch] = csubstream; - - ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, - soc_runtime->platform->dev, - size, &csubstream->dma_buffer); - if (ret) - goto capture_alloc_err; - - ret = regmap_write(drvdata->lpaif_map, - LPAIF_WRDMACTL_REG(v, data->wrdma_ch), 0); + ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, dev, size, + &csubstream->dma_buffer); if (ret) { - dev_err(soc_runtime->dev, - "%s() error writing to wrdmactl reg: %d\n", - __func__, ret); - goto capture_reg_err; + dev_err(dev, "can't alloc capture dma buffer\n"); + if (psubstream) + snd_dma_free_pages(&psubstream->dma_buffer); + return ret; } }

return 0; - -capture_reg_err: - if (csubstream) - snd_dma_free_pages(&csubstream->dma_buffer); - -capture_alloc_err: - if (psubstream) - snd_dma_free_pages(&psubstream->dma_buffer); - - playback_alloc_err: - dev_err(soc_runtime->dev, "Cannot allocate buffer(s)\n"); - - return ret; }

static void lpass_platform_pcm_free(struct snd_pcm *pcm) { - struct snd_soc_pcm_runtime *rt; - struct lpass_data *drvdata; - struct lpass_pcm_data *data; - struct lpass_variant *v; struct snd_pcm_substream *substream; - int ch, i; + int i;

for (i = 0; i < ARRAY_SIZE(pcm->streams); i++) { substream = pcm->streams[i].substream; if (substream) { - rt = substream->private_data; - data = snd_soc_pcm_get_drvdata(rt); - drvdata = snd_soc_platform_get_drvdata(rt->platform); - - ch = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) - ? data->rdma_ch - : data->wrdma_ch; - v = drvdata->variant; - drvdata->substream[ch] = NULL; - if (v->free_dma_channel) - v->free_dma_channel(drvdata, ch); - snd_dma_free_pages(&substream->dma_buffer); substream->dma_buffer.area = NULL; substream->dma_buffer.addr = 0;

The patch

ASoC: lpass-cpu: add module licence and description

has been applied to the asoc tree at

git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git

All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying to this mail.

Thanks, Mark

From 94201798dbce1cfd242407f1f422819a735c838f Mon Sep 17 00:00:00 2001

From: Srinivas Kandagatla srinivas.kandagatla@linaro.org Date: Mon, 31 Oct 2016 11:25:45 +0000 Subject: [PATCH] ASoC: lpass-cpu: add module licence and description

This patch adds module licence to lpass-cpu driver, without this patch lpass-cpu module would taint with below error:

snd_soc_lpass_cpu: module license 'unspecified' taints kernel. Disabling lock debugging due to kernel taint snd_soc_lpass_cpu: Unknown symbol regmap_write (err 0) snd_soc_lpass_cpu: Unknown symbol devm_kmalloc (err 0) ...

Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Acked-by: Kenneth Westfield kwestfie@codeaurora.org Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/qcom/lpass-cpu.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/sound/soc/qcom/lpass-cpu.c b/sound/soc/qcom/lpass-cpu.c index 3cde9fb977fa..eff3f9a8b685 100644 --- a/sound/soc/qcom/lpass-cpu.c +++ b/sound/soc/qcom/lpass-cpu.c @@ -586,3 +586,6 @@ int asoc_qcom_lpass_cpu_platform_remove(struct platform_device *pdev) return 0; } EXPORT_SYMBOL_GPL(asoc_qcom_lpass_cpu_platform_remove); + +MODULE_DESCRIPTION("QTi LPASS CPU Driver"); +MODULE_LICENSE("GPL v2");