On 04/06/16 16:21, Petr Kulhavy wrote:
This adds DT support for the TI DA8xx/OMAP-L1x/AM17xx/AM18xx McBSP driver.
Signed-off-by: Petr Kulhavy petr@barix.com
sound/soc/davinci/Kconfig | 6 ++- sound/soc/davinci/davinci-i2s.c | 106 ++++++++++++++++++++++++++++++++++------ 2 files changed, 96 insertions(+), 16 deletions(-)
diff --git a/sound/soc/davinci/Kconfig b/sound/soc/davinci/Kconfig index 50ca291cc225..6b732d8e5896 100644 --- a/sound/soc/davinci/Kconfig +++ b/sound/soc/davinci/Kconfig @@ -16,7 +16,11 @@ config SND_EDMA_SOC - DRA7xx family
config SND_DAVINCI_SOC_I2S
- tristate
- tristate "DaVinci Multichannel Buffered Serial Port (McBSP) support"
- depends on SND_EDMA_SOC
- help
Say Y or M here if you want to have support for McBSP IP found inTexas Instruments DaVinci DA850 SoCs.config SND_DAVINCI_SOC_MCASP tristate "Multichannel Audio Serial Port (McASP) support" diff --git a/sound/soc/davinci/davinci-i2s.c b/sound/soc/davinci/davinci-i2s.c index ec98548a5fc9..2ebfe86dd584 100644 --- a/sound/soc/davinci/davinci-i2s.c +++ b/sound/soc/davinci/davinci-i2s.c @@ -4,9 +4,15 @@
- Author: Vladimir Barinov, vbarinov@embeddedalley.com
- Copyright: (C) 2007 MontaVista Software, Inc., source@mvista.com
- DT support (c) 2016 Petr Kulhavy, Barix AG petr@barix.com
based on davinci-mcasp.c DT support
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License version 2 as
- published by the Free Software Foundation.
- TODO:
- on DA850 implement HW FIFOs instead of DMA into DXR and DRR registers
The BFIFO looks identical to AFIFO for McASP...
*/
#include <linux/init.h> @@ -648,15 +654,82 @@ static const struct snd_soc_component_driver davinci_i2s_component = { .name = "davinci-i2s", };
+static struct snd_platform_data* +davinci_i2s_set_pdata_from_of(struct platform_device *pdev) +{
- struct snd_platform_data *pdata = NULL;
- struct device_node *np;
- struct of_phandle_args dma_spec;
- int ret;
- if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
return dev_get_platdata(&pdev->dev);- pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
- if (!pdata)
return ERR_PTR(-ENOMEM);- np = pdev->dev.of_node;
- ret = of_property_match_string(np, "dma-names", "tx");
- if (ret >= 0) {
ret = of_parse_phandle_with_args(np, "dmas", "#dma-cells", ret,&dma_spec);if (ret >= 0)pdata->tx_dma_channel = dma_spec.args[0];- }
- ret = of_property_match_string(np, "dma-names", "rx");
- if (ret >= 0) {
ret = of_parse_phandle_with_args(np, "dmas", "#dma-cells", ret,&dma_spec);if (ret >= 0)pdata->rx_dma_channel = dma_spec.args[0];- }
Why would you do this? If we booted with DT the only thing needed by the edma-pcm (dmaengine) is the name of the DMA channel...
- /* optional parameters */
- pdata->enable_channel_combine =
of_property_read_bool(np, "channel-combine");
This can only be done when the McBSP is used in DSP_x mode since this will make the McBSP to transmit the stereo audio as mono on the bus.
After a quick look at the relevant parts in the driver, I think most of the things are pretty much broken or at least they are not totally correct. McBSP do support real I2S (SRGR:FWID), and the phase setup is wrong in the code. IMO. I don't have HW to test the daVinci-MCBSP or the ASP so I can not comment on how well things are working.
- /*
* pdata->clk_input_pin is deliberately not exported to DT* and the default value of the clk_input_pin is MCBSP_CLKR.* The value MCBSP_CLKS makes no sense as it turns the CPU* to a bit clock master in the SND_SOC_DAIFMT_CBM_CFS mode* where it should be bit clock slave!*/
Interesting. As a whole the clock selection part is mostly broken in the driver... It would be better to add davinci_i2s_set_sysclk() to deal with the system clock configuration.
- return pdata;
+}
static int davinci_i2s_probe(struct platform_device *pdev) {
- struct snd_platform_data *pdata; struct davinci_mcbsp_dev *dev; struct resource *mem, *res; void __iomem *io_base; int *dma; int ret;
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- pdata = davinci_i2s_set_pdata_from_of(pdev);
- if (IS_ERR(pdata)) {
dev_err(&pdev->dev, "Error populating platform data, err %ld\n",PTR_ERR(pdata));return PTR_ERR(pdata);- }
- mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mpu");
- if (!mem) {
dev_warn(&pdev->dev,"\"mpu\" mem resource not found, using index 0\n");mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);if (!mem) {dev_err(&pdev->dev, "no mem resource?\n");return -ENODEV;}- }
- io_base = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(io_base)) return PTR_ERR(io_base);
@@ -680,25 +753,21 @@ static int davinci_i2s_probe(struct platform_device *pdev) (dma_addr_t)(mem->start + DAVINCI_MCBSP_DRR_REG);
/* first TX, then RX */
- res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
- if (!res) {
dev_err(&pdev->dev, "no DMA resource\n");ret = -ENXIO;goto err_release_clk;- } dma = &dev->dma_request[SNDRV_PCM_STREAM_PLAYBACK];
- *dma = res->start; dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].filter_data = dma;
- res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
- if (res)
*dma = res->start;- else
*dma = pdata->tx_dma_channel;
Please follow the way davinci-mcasp does it right now: dma_data = &mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK]; ... dma = &mcasp->dma_request[SNDRV_PCM_STREAM_PLAYBACK]; res = platform_get_resource(pdev, IORESOURCE_DMA, 0); if (res) *dma = res->start; else *dma = pdata->tx_dma_channel;
/* dmaengine filter data for DT and non-DT boot */ if (pdev->dev.of_node) dma_data->filter_data = "tx"; else dma_data->filter_data = dma;
while we are here, I think the tx/rx_dma_channel is something we should just get rid of. It is not used as far as I can tell. Something like this would do I think: dma_data = &mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK]; ... res = platform_get_resource(pdev, IORESOURCE_DMA, 0); if (res) { dma = &mcasp->dma_request[SNDRV_PCM_STREAM_PLAYBACK]; *dma = res->start; dma_data->filter_data = dma; } else if (pdev->dev.of_node) { dma_data->filter_data = "tx"; } else { dev_err(&pdev->dev, "Missing DMA tx resource\n"); return -ENODEV; }
- res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
- if (!res) {
dev_err(&pdev->dev, "no DMA resource\n");ret = -ENXIO;goto err_release_clk;- } dma = &dev->dma_request[SNDRV_PCM_STREAM_CAPTURE];
- *dma = res->start; dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].filter_data = dma;
- res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
- if (res)
*dma = res->start;- else
*dma = pdata->rx_dma_channel;
same comment as for the TX dma part.
dev->dev = &pdev->dev; dev_set_drvdata(&pdev->dev, dev); @@ -737,11 +806,18 @@ static int davinci_i2s_remove(struct platform_device *pdev) return 0; }
+static const struct of_device_id davinci_mcbsp_match[] = {
- { .compatible = "ti,da850-mcbsp-audio" },
I would drop the "-audio" for the binding...
- {},
+}; +MODULE_DEVICE_TABLE(of, davinci_mcbsp_match);
static struct platform_driver davinci_mcbsp_driver = { .probe = davinci_i2s_probe, .remove = davinci_i2s_remove, .driver = { .name = "davinci-mcbsp",
.of_match_table = of_match_ptr(davinci_mcbsp_match),
The driver calls itself davinci-i2s.c and the prefixes internally used are davinci_i2s_*. The driver name is "davinci-mcbsp". And it is basically a driver for daVinci ASP (the McBSP additions are not configured at all).
I still think we should keep the davinci_i2s_* when adding new code, or rename the whole driver and it's prefixes to something more sensible?
}, };