[alsa-devel] [PATCH 3/4] ASoC sst: Add mid machine driver
This patch adds the mic machine driver The mid machine driver glues the msic and mid_platfrom driver to form the asoc sound driver
Signed-off-by: Vinod Koul vinod.koul@intel.com Signed-off-by: Harsha Priya priya.harsha@intel.com --- sound/soc/mid-x86/mid_machine.c | 317 +++++++++++++++++++++++++++++++++++ sound/soc/mid-x86/mid_machine.h | 37 ++++ sound/soc/mid-x86/mid_machine_lib.c | 54 ++++++ 3 files changed, 408 insertions(+), 0 deletions(-) create mode 100644 sound/soc/mid-x86/mid_machine.c create mode 100644 sound/soc/mid-x86/mid_machine.h create mode 100644 sound/soc/mid-x86/mid_machine_lib.c
diff --git a/sound/soc/mid-x86/mid_machine.c b/sound/soc/mid-x86/mid_machine.c new file mode 100644 index 0000000..36786ce --- /dev/null +++ b/sound/soc/mid-x86/mid_machine.c @@ -0,0 +1,317 @@ +/* + * mid_machine.c - Intel MID Machine driver + * + * Copyright (C) 2010 Intel Corp + * Author: Vinod Koul vinod.koul@intel.com + * Author: Harsha Priya priya.harsha@intel.com + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/init.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <sound/pcm.h> +#include <sound/pcm_params.h> +#include <sound/soc.h> +#include "../codecs/msic.h" +#include "mid_machine.h" + +struct mid_mfld_device { + struct platform_device *mid_platform_device; + struct platform_device *mid_codec_device; + struct platform_device *mid_soc_device; +}; + +static unsigned int hs_switch; +static unsigned int lo_dac; + +/*sound card controls*/ +static const char *headset_switch_text[] = {"Earpiece", "Headset"}; + +static const char *lo_text[] = {"Vibra", "Headset", "IHF", "None"}; + +static const struct soc_enum headset_enum = + SOC_ENUM_SINGLE_EXT(2, headset_switch_text); + +static const struct soc_enum lo_enum = + SOC_ENUM_SINGLE_EXT(4, lo_text); + +static int headset_get_switch(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + ucontrol->value.integer.value[0] = hs_switch; + return 0; +} + +static int headset_set_switch(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol); + + if (ucontrol->value.integer.value[0] == hs_switch) + return 0; + + if (ucontrol->value.integer.value[0]) { + pr_debug("hs_set HS path\n"); + snd_soc_dapm_enable_pin(&codec->dapm, "HPOUTL"); + snd_soc_dapm_enable_pin(&codec->dapm, "HPOUTR"); + snd_soc_dapm_disable_pin(&codec->dapm, "EPOUT"); + } else { + pr_debug("hs_set EP path\n"); + snd_soc_dapm_disable_pin(&codec->dapm, "HPOUTL"); + snd_soc_dapm_disable_pin(&codec->dapm, "HPOUTR"); + snd_soc_dapm_enable_pin(&codec->dapm, "EPOUT"); + } + snd_soc_dapm_sync(&codec->dapm); + hs_switch = ucontrol->value.integer.value[0]; + + return 0; +} + +static void lo_enable_out_pins(struct snd_soc_codec *codec) +{ + snd_soc_dapm_enable_pin(&codec->dapm, "IHFOUTL"); + snd_soc_dapm_enable_pin(&codec->dapm, "IHFOUTR"); + snd_soc_dapm_enable_pin(&codec->dapm, "LINEOUTL"); + snd_soc_dapm_enable_pin(&codec->dapm, "LINEOUTR"); + snd_soc_dapm_enable_pin(&codec->dapm, "VIB1OUT"); + snd_soc_dapm_enable_pin(&codec->dapm, "VIB2OUT"); + if (hs_switch) { + snd_soc_dapm_enable_pin(&codec->dapm, "HPOUTL"); + snd_soc_dapm_enable_pin(&codec->dapm, "HPOUTR"); + snd_soc_dapm_disable_pin(&codec->dapm, "EPOUT"); + } else { + snd_soc_dapm_disable_pin(&codec->dapm, "HPOUTL"); + snd_soc_dapm_disable_pin(&codec->dapm, "HPOUTR"); + snd_soc_dapm_enable_pin(&codec->dapm, "EPOUT"); + } +} + +static int lo_get_switch(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + ucontrol->value.integer.value[0] = lo_dac; + return 0; +} + +static int lo_set_switch(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol); + + if (ucontrol->value.integer.value[0] == lo_dac) + return 0; + + /* + * we dont want to work with last state of lineout so just enable all + * pins and then disable pins not required + */ + lo_enable_out_pins(codec); + switch (ucontrol->value.integer.value[0]) { + case 0: + pr_debug("set vibra path\n"); + snd_soc_dapm_disable_pin(&codec->dapm, "VIB1OUT"); + snd_soc_dapm_disable_pin(&codec->dapm, "VIB2OUT"); + snd_soc_update_bits(codec, MSIC_LOCTL, 0x66, 0); + break; + + case 1: + pr_debug("set hs path\n"); + snd_soc_dapm_disable_pin(&codec->dapm, "HPOUTL"); + snd_soc_dapm_disable_pin(&codec->dapm, "HPOUTR"); + snd_soc_dapm_disable_pin(&codec->dapm, "EPOUT"); + snd_soc_update_bits(codec, MSIC_LOCTL, 0x66, 0x22); + break; + + case 2: + pr_debug("set spkr path\n"); + snd_soc_dapm_disable_pin(&codec->dapm, "IHFOUTL"); + snd_soc_dapm_disable_pin(&codec->dapm, "IHFOUTR"); + snd_soc_update_bits(codec, MSIC_LOCTL, 0x66, 0x44); + break; + + case 3: + pr_debug("set null path\n"); + snd_soc_dapm_disable_pin(&codec->dapm, "LINEOUTL"); + snd_soc_dapm_disable_pin(&codec->dapm, "LINEOUTR"); + snd_soc_update_bits(codec, MSIC_LOCTL, 0x66, 0x66); + break; + } + snd_soc_dapm_sync(&codec->dapm); + lo_dac = ucontrol->value.integer.value[0]; + return 0; +} + +static const struct snd_kcontrol_new mid_snd_controls[] = { + SOC_ENUM_EXT("Playback Switch", headset_enum, + headset_get_switch, headset_set_switch), + SOC_ENUM_EXT("Lineout Mux", lo_enum, + lo_get_switch, lo_set_switch), +}; + +static int msic_init(struct snd_soc_pcm_runtime *runtime) +{ + struct snd_soc_codec *codec = runtime->codec; + struct snd_soc_dapm_context *dapm = &codec->dapm; + int ret_val; + + ret_val = snd_soc_add_controls(codec, mid_snd_controls, + ARRAY_SIZE(mid_snd_controls)); + if (ret_val) { + pr_err("soc_add_controls failed %d", ret_val); + return ret_val; + } + /*default is earpiece pin, userspace sets it explcitly*/ + snd_soc_dapm_disable_pin(dapm, "HPOUTL"); + snd_soc_dapm_disable_pin(dapm, "HPOUTR"); + /*default is lineout NC, userspace sets it explcitly*/ + snd_soc_dapm_disable_pin(dapm, "LINEOUTL"); + snd_soc_dapm_disable_pin(dapm, "LINEOUTR"); + return snd_soc_dapm_sync(dapm); + lo_dac = 3; + hs_switch = 0; +} + +struct snd_soc_dai_link mfld_msic_dailink[] = { + { + .name = "Intel MSIC Headset", + .stream_name = "Codec", + .cpu_dai_name = "Headset-cpu-dai", + .codec_dai_name = "Intel MSIC Headset", + .codec_name = "mid-msic-codec", + .platform_name = "mid-audio-platform", + .init = msic_init, + }, + { + .name = "Intel MSIC Speaker", + .stream_name = "Speaker", + .cpu_dai_name = "Speaker-cpu-dai", + .codec_dai_name = "Intel MSIC Speaker", + .codec_name = "mid-msic-codec", + .platform_name = "mid-audio-platform", + .init = NULL, + }, + { + .name = "Intel MSIC Vibra1", + .stream_name = "Vibra1", + .cpu_dai_name = "Vibra 1-cpu-dai", + .codec_dai_name = "Intel MSIC Vibra1", + .codec_name = "mid-msic-codec", + .platform_name = "mid-audio-platform", + .init = NULL, + }, + { + .name = "Intel MSIC Vibra2", + .stream_name = "Vibra2", + .cpu_dai_name = "Vibra 2-cpu-dai", + .codec_dai_name = "Intel MSIC Vibra2", + .codec_name = "mid-msic-codec", + .platform_name = "mid-audio-platform", + .init = NULL, + }, +}; + +/* SoC card */ +static struct snd_soc_card snd_soc_card_mfld = { + .name = "mid_msic_audio", + .dai_link = mfld_msic_dailink, + .num_links = ARRAY_SIZE(mfld_msic_dailink), +}; + +int __devinit snd_intelmid_mc_probe(struct platform_device *pdev) +{ + struct mid_mfld_device *dev_data; + int ret_val = 0; + + pr_debug("snd_intelmid_mc_probe called\n"); + + dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL); + if (!dev_data) { + pr_err("snd_intelmid_mc_probe mem alloc fail\n"); + return -ENOMEM; + } + + ret_val = create_device(&dev_data->mid_platform_device, + "mid-audio-platform", NULL); + if (ret_val) + return ret_val; + + ret_val = create_device(&dev_data->mid_codec_device, + "mid-msic-codec", NULL); + if (ret_val) + goto unreg_platform; + + ret_val = create_device(&dev_data->mid_soc_device, + "soc-audio", &snd_soc_card_mfld); + if (ret_val) + goto unreg_codec; + + platform_set_drvdata(pdev, dev_data); + + pr_debug("successfully exited probe\n"); + return ret_val; +unreg_codec: + platform_device_unregister(dev_data->mid_codec_device); +unreg_platform: + platform_device_unregister(dev_data->mid_platform_device); + return ret_val; +} + +static int snd_intelmid_remove(struct platform_device *pdev) +{ + struct mid_mfld_device *dev_data = platform_get_drvdata(pdev); + pr_debug("snd_intelmid_remove called\n"); + + platform_device_unregister(dev_data->mid_soc_device); + platform_device_unregister(dev_data->mid_platform_device); + platform_device_unregister(dev_data->mid_codec_device); + platform_set_drvdata(pdev, NULL); + return 0; +} + +static struct platform_driver snd_intelmid_mc_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "msic_audio", + }, + .probe = snd_intelmid_mc_probe, + .remove = __devexit_p(snd_intelmid_remove), +}; + +static int __init intelmidmc_soc_init(void) +{ + pr_debug("intelmidmc_soc_init called\n"); + return platform_driver_register(&snd_intelmid_mc_driver); +} +module_init(intelmidmc_soc_init); + +static void __exit intelmidmc_soc_exit(void) +{ + pr_debug("intelmidmc_soc_exit called\n"); + platform_driver_unregister(&snd_intelmid_mc_driver); +} +module_exit(intelmidmc_soc_exit); + +MODULE_DESCRIPTION("ASoC Intel(R) MID Machine driver"); +MODULE_AUTHOR("Vinod Koul vinod.koul@intel.com"); +MODULE_AUTHOR("Harsha Priya priya.harsha@intel.com"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("mid-machine"); diff --git a/sound/soc/mid-x86/mid_machine.h b/sound/soc/mid-x86/mid_machine.h new file mode 100644 index 0000000..34dbbdd --- /dev/null +++ b/sound/soc/mid-x86/mid_machine.h @@ -0,0 +1,37 @@ +/* + * mid_machine.h - Intel MID Machine driver header file + * + * Copyright (C) 2010 Intel Corp + * Author: Vinod Koul vinod.koul@intel.com + * Author: Harsha Priya priya.harsha@intel.com + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * + */ + +#ifndef __MID_MACHINEDRV_H__ +#define __MID_MACHINEDRV_H__ + +#define MID_MONO 1 +#define MID_STEREO 2 +#define MID_MAX_CAP 5 + +int create_device(struct platform_device **device, char *name, + void *drv_data); +#endif + diff --git a/sound/soc/mid-x86/mid_machine_lib.c b/sound/soc/mid-x86/mid_machine_lib.c new file mode 100644 index 0000000..fce2861 --- /dev/null +++ b/sound/soc/mid-x86/mid_machine_lib.c @@ -0,0 +1,54 @@ +/* + * mid_machine_lib.c - Intel Machine driver library functions + * should be reused in other mid machine drivers + * + * Copyright (C) 2010 Intel Corp + * Author: Vinod Koul vinod.koul@intel.com + * Author: Harsha Priya priya.harsha@intel.com + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/platform_device.h> + +int create_device(struct platform_device **device, char *name, + void *drv_data) +{ + int ret_val = 0; + + pr_debug("%s device creation...", name); + + *device = platform_device_alloc(name, -1); + if (!*device) { + pr_err("%s device allocation failed\n", name); + return -ENOMEM; + } + + if (drv_data) + platform_set_drvdata(*device, drv_data); + + ret_val = platform_device_add(*device); + if (ret_val) { + pr_err("Unable to add platform device\n"); + platform_device_put(*device); + } + pr_debug("%s...created\n", name); + return ret_val; +}
On Thu, Dec 30, 2010 at 04:43:13PM +0530, Vinod Koul wrote:
This patch adds the mic machine driver The mid machine driver glues the msic and mid_platfrom driver to form the asoc sound driver
So, this isn't actually doing any sort of interface with your BIOS or otherwise doing anything system-specific. If this is intended to be a generic driver that manages the interaction with your BIOS then I'd expect to see something like that. If it's a driver for a specific system then I'd expect the driver to say what it's a driver for.
Also, looking at your CODEC driver I'm not seeing anything that looks like the handling for the three "nameless" CODEC vendors you've got - given that you've got vendor workarounds in the code there this is really surprising.
This patch adds the mic machine driver The mid machine driver glues the msic and mid_platfrom driver to form the
asoc sound driver
So, this isn't actually doing any sort of interface with your BIOS or otherwise doing anything system-specific.
It is not
If this is intended to be a generic driver that manages the interaction with your BIOS then I'd expect to see something like that. If it's a driver for a specific system then I'd expect the driver to say what it's a driver for.
No, per your suggestion we made it machine specific driver. Yes will rename it to mid_machine_mfld as this is Medfield specific machine driver Does that fix your concern?
Also, looking at your CODEC driver I'm not seeing anything that looks like the handling for the three "nameless" CODEC vendors you've got - given that you've got vendor workarounds in the code there this is really surprising.
The msic.c is msic codec which is specific to Medfield platform only. The other three codecs are for Moorestown and we will add them ( 3 separate codec drivers) when we add Moorestown machine (next after completing this)
~Vinod
On Mon, Jan 03, 2011 at 11:09:16AM +0530, Koul, Vinod wrote:
If this is intended to be a generic driver that manages the interaction with your BIOS then I'd expect to see something like that. If it's a driver for a specific system then I'd expect the driver to say what it's a driver for.
No, per your suggestion we made it machine specific driver. Yes will rename it to mid_machine_mfld as this is Medfield specific machine driver Does that fix your concern?
That helps but in that case you also need to remove all the device registration stuff except for the actual machine driver from the init and exit functions. The CPU stuff is all a fixed property of the CPU and should be reigstered by the architecture code (possibly with some control for the individual machine), the CODEC should be being enumerated by whatever normally does that. The only thing this driver should be doing is specifying how these things are connected.
Also, looking at your CODEC driver I'm not seeing anything that looks like the handling for the three "nameless" CODEC vendors you've got - given that you've got vendor workarounds in the code there this is really surprising.
The msic.c is msic codec which is specific to Medfield platform only. The other three codecs are for Moorestown and we will add them ( 3 separate codec drivers) when we add Moorestown machine (next after completing this)
What exactly is the msic CODEC? Given the references to non-specific "vendor" registers it doesn't sound like a particular CODEC driver.
If this is intended to be a generic driver that manages the interaction with your BIOS then I'd expect to see something like that. If it's a driver for a specific system then I'd expect the driver to say what it's a driver for.
No, per your suggestion we made it machine specific driver. Yes will rename
it
to mid_machine_mfld as this is Medfield specific machine driver Does that fix your concern?
That helps but in that case you also need to remove all the device registration stuff except for the actual machine driver from the init and exit functions. The CPU stuff is all a fixed property of the CPU and should be reigstered by the architecture code (possibly with some control for the individual machine), the CODEC should be being enumerated by whatever normally does that. The only thing this driver should be doing is specifying how these things are connected.
Yes, this patch had only the machine specific controls and dai link. It also creates the audio platform devices soc-audio platform and codec device. It doesn't do anything else
Also, looking at your CODEC driver I'm not seeing anything that looks like the handling for the three "nameless" CODEC vendors you've got - given that you've got vendor workarounds in the code there this is really surprising.
The msic.c is msic codec which is specific to Medfield platform only. The
other
three codecs are for Moorestown and we will add them ( 3 separate codec
drivers)
when we add Moorestown machine (next after completing this)
What exactly is the msic CODEC? Given the references to non-specific "vendor" registers it doesn't sound like a particular CODEC driver.
Since Medfield platform is not declared yet we can't reveal the name of the codec vendor. The Moorestown codecs which we will add will not be nameless as this one and we will add as vendorversion.c format as in current codec drivers. I will replace this msic driver name once the platform is publically declared.
~Vinod
On Mon, Jan 03, 2011 at 09:31:26PM +0530, Koul, Vinod wrote:
That helps but in that case you also need to remove all the device registration stuff except for the actual machine driver from the init and exit functions. The CPU stuff is all a fixed property of the CPU and should be reigstered by the architecture code (possibly with some control for the individual machine), the CODEC should be being enumerated by whatever normally does that. The only thing this driver should be doing is specifying how these things are connected.
Yes, this patch had only the machine specific controls and dai link. It also creates the audio platform devices soc-audio platform and codec device. It doesn't do anything else
This is preceisely the problem. As I said the machine driver should only be instantiating the machine driver. Actual physical devices should be being instnantiated using the relevant buses.
Please look at how other platforms are doing this; you should be following the same process.
What exactly is the msic CODEC? Given the references to non-specific "vendor" registers it doesn't sound like a particular CODEC driver.
Since Medfield platform is not declared yet we can't reveal the name of the codec vendor. The Moorestown codecs which we will add will not be nameless as this one and we will add as vendorversion.c format as in current codec drivers. I will replace this msic driver name once the platform is publically declared.
So you're saying this is a driver for a specific device that you're releasing under a code name? That's not what the code looks like. None of this seems terribly clever for mainline; there's too many things about these drivers don't look like what you'd expect embedded audio drivers for Linux to look like from a 1000 foot level.
Yes, this patch had only the machine specific controls and dai link. It also creates the audio platform devices soc-audio platform and codec
device.
It doesn't do anything else
This is preceisely the problem. As I said the machine driver should only be instantiating the machine driver. Actual physical devices should be being instnantiated using the relevant buses.
Please look at how other platforms are doing this; you should be following the same process.
Thanks, I will add the soc-audio only and move the others to core. So now this machine driver will only add machine controls and dai link along with soc-audio device. Would that suffice
What exactly is the msic CODEC? Given the references to non-specific "vendor" registers it doesn't sound like a particular CODEC driver.
Since Medfield platform is not declared yet we can't reveal the name of the codec vendor. The Moorestown codecs which we will add will not be nameless as this one and we will add as vendorversion.c format as in current codec drivers. I will replace this msic driver name once the platform is publically declared.
So you're saying this is a driver for a specific device that you're releasing under a code name? That's not what the code looks like. None of this seems terribly clever for mainline; there's too many things about these drivers don't look like what you'd expect embedded audio drivers for Linux to look like from a 1000 foot level.
This is codec from TI and I will remove the msic name now. It will now be ti-sn95031.c Does this address your concern on this issue?
~Vinod
On Mon, Jan 03, 2011 at 11:04:11PM +0530, Koul, Vinod wrote:
Thanks, I will add the soc-audio only and move the others to core. So now this machine driver will only add machine controls and dai link along with soc-audio device. Would that suffice
That sounds reasonable; I'd need to see the code to confirm.
This is codec from TI and I will remove the msic name now. It will now be ti-sn95031.c Does this address your concern on this issue?
Normally Linux just uses the part name so that'd just be sn95031 - look at the other CODEC drivers for example. In general you should try to make your code look as similar as possible to what other systems are doing.
On Thu, Dec 30, 2010 at 04:43:13PM +0530, Vinod Koul wrote:
+int create_device(struct platform_device **device, char *name,
void *drv_data)+{
- int ret_val = 0;
I didn't notice this when I read the driver originally as the file appears after the actual machine driver: this is is a namespace violation if nothing else and is not appropraite for doing in a platform specific subsystem like this; if this is required it should be done in the device core (and be platform device specific), though I rather suspect the existing helper functions do the job just fine.
participants (3)
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Koul, Vinod -
Mark Brown -
Vinod Koul