Re: [PATCH V3 2/8] soundwire: amd: Add support for AMD Manager driver

[<Claudiu.Beznea@microchip.com>]

On 20.02.2023 12:04, Vijendar Mukunda wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> AMD ACP(v6.x) IP block has two SoundWire manager devices.
> Add support for
>   - Manager driver probe & remove sequence
>   - Helper functions to enable/disable interrupts, Initialize sdw manager,
>     enable sdw pads
>   - Manager driver sdw_master_ops & port_ops callbacks
> 
> Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
> ---
>  drivers/soundwire/amd_manager.c   | 761 ++++++++++++++++++++++++++++++
>  drivers/soundwire/amd_manager.h   | 252 ++++++++++
>  include/linux/soundwire/sdw_amd.h |  67 +++
>  3 files changed, 1080 insertions(+)
>  create mode 100644 drivers/soundwire/amd_manager.c
>  create mode 100644 drivers/soundwire/amd_manager.h
>  create mode 100644 include/linux/soundwire/sdw_amd.h
> 
> diff --git a/drivers/soundwire/amd_manager.c b/drivers/soundwire/amd_manager.c
> new file mode 100644
> index 000000000000..b820e04ca09f
> --- /dev/null
> +++ b/drivers/soundwire/amd_manager.c
> @@ -0,0 +1,761 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * SoundWire AMD Manager driver
> + *
> + * Copyright 2023 Advanced Micro Devices, Inc.
> + */
> +
> +#include <linux/completion.h>
> +#include <linux/device.h>
> +#include <linux/io.h>
> +#include <linux/jiffies.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/soundwire/sdw.h>
> +#include <linux/soundwire/sdw_registers.h>
> +#include <linux/wait.h>
> +#include <sound/pcm_params.h>
> +#include <sound/soc.h>
> +#include "bus.h"
> +#include "amd_manager.h"
> +
> +#define DRV_NAME "amd_sdw_manager"
> +
> +#define to_amd_sdw(b)  container_of(b, struct amd_sdw_manager, bus)
> +
> +static void amd_enable_sdw_pads(struct amd_sdw_manager *amd_manager)
> +{
> +       u32 sw_pad_pulldown_val;
> +       u32 val;
> +
> +       mutex_lock(amd_manager->acp_sdw_lock);
> +       val = acp_reg_readl(amd_manager->acp_mmio + ACP_SW_PAD_KEEPER_EN);
> +       val |= amd_manager->reg_mask->sw_pad_enable_mask;
> +       acp_reg_writel(val, amd_manager->acp_mmio + ACP_SW_PAD_KEEPER_EN);
> +       usleep_range(1000, 1500);
> +
> +       sw_pad_pulldown_val = acp_reg_readl(amd_manager->acp_mmio + ACP_PAD_PULLDOWN_CTRL);
> +       sw_pad_pulldown_val &= amd_manager->reg_mask->sw_pad_pulldown_mask;
> +       acp_reg_writel(sw_pad_pulldown_val, amd_manager->acp_mmio + ACP_PAD_PULLDOWN_CTRL);
> +       mutex_unlock(amd_manager->acp_sdw_lock);
> +}
> +
> +static int amd_init_sdw_manager(struct amd_sdw_manager *amd_manager)
> +{
> +       u32 val;
> +       u32 timeout = 0;
> +       u32 retry_count = 0;
> +
> +       acp_reg_writel(AMD_SDW_ENABLE, amd_manager->mmio + ACP_SW_EN);
> +       do {
> +               val = acp_reg_readl(amd_manager->mmio + ACP_SW_EN_STATUS);
> +               if (val)
> +                       break;
> +               usleep_range(10, 50);
> +       } while (retry_count++ < AMD_SDW_STAT_MAX_RETRY_COUNT);

Can't these timeout loops be addressed w/ read_poll_timeout()?

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