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Date:   Mon, 18 Sep 2023 14:31:54 +0300
From:   Heikki Krogerus <heikki.krogerus@linux.intel.com>
To:     Abdel Alkuor <alkuor@gmail.com>
Cc:     krzysztof.kozlowski+dt@linaro.org, bryan.odonoghue@linaro.org,
        gregkh@linuxfoundation.org, robh+dt@kernel.org,
        linux-usb@vger.kernel.org, devicetree@vger.kernel.org,
        conor+dt@kernel.org, linux-kernel@vger.kernel.org,
        abdelalkuor@geotab.com
Subject: Re: [PATCH v5 04/15] USB: typec: Load TPS25750 patch bundle
Message-ID: <ZQg1KjinxBRxwUSM@kuha.fi.intel.com>
References: <20230917152639.21443-1-alkuor@gmail.com>
 <20230917152639.21443-5-alkuor@gmail.com>
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In-Reply-To: <20230917152639.21443-5-alkuor@gmail.com>
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On Sun, Sep 17, 2023 at 11:26:28AM -0400, Abdel Alkuor wrote:
> From: Abdel Alkuor <abdelalkuor@geotab.com>
> 
> TPS25750 controller requires a binary to be loaded with a configuration
> binary by an EEPROM or a host.
> 
> Appling a patch bundling using a host is implemented based on the flow
> diagram pg.62 in TPS25750 host interface manual.
> https://www.ti.com/lit/ug/slvuc05a/slvuc05a.pdf
> 
> The flow diagram can be summarized as following:
> - Start the patch loading sequence with patch bundle information by
>   executing PBMs
> - Write the whole patch at once
> - When writing the patch fails, execute PBMe which instructs the PD controller
>   to end the patching process
> - After writing the patch successfully, execute PBMc which verifies the patch
>   integrity and applies the patch internally
> - Wait for the device to switch into APP mode (normal operation)
> 
> The execuation flow diagram polls the events register and then polls the
> corresponding register related to the event as well before advancing to the next
> state. Polling the events register is a redundant step, in this implementation
> only the corresponding register related to the event is polled.
> 
> Signed-off-by: Abdel Alkuor <abdelalkuor@geotab.com>
> ---
>  drivers/usb/typec/tipd/core.c | 237 +++++++++++++++++++++++++++++++++-
>  1 file changed, 236 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
> index 6d2151325fbb..fea139c72d6d 100644
> --- a/drivers/usb/typec/tipd/core.c
> +++ b/drivers/usb/typec/tipd/core.c
> @@ -17,6 +17,7 @@
>  #include <linux/usb/typec_altmode.h>
>  #include <linux/usb/role.h>
>  #include <linux/workqueue.h>
> +#include <linux/firmware.h>
>  
>  #include "tps6598x.h"
>  #include "trace.h"
> @@ -43,6 +44,23 @@
>  /* TPS_REG_SYSTEM_CONF bits */
>  #define TPS_SYSCONF_PORTINFO(c)		((c) & 7)
>  
> +/*
> + * BPMs task timeout, recommended 5 seconds
> + * pg.48 TPS2575 Host Interface Technical Reference
> + * Manual (Rev. A)
> + * https://www.ti.com/lit/ug/slvuc05a/slvuc05a.pdf
> + */
> +#define TPS_BUNDLE_TIMEOUT	0x32
> +
> +/* BPMs return code */
> +#define TPS_TASK_BPMS_INVALID_BUNDLE_SIZE	0x4
> +#define TPS_TASK_BPMS_INVALID_SLAVE_ADDR	0x5
> +#define TPS_TASK_BPMS_INVALID_TIMEOUT		0x6
> +
> +/* PBMc data out */
> +#define TPS_PBMC_RC	0 /* Return code */
> +#define TPS_PBMC_DPCS	2 /* device patch complete status */
> +
>  enum {
>  	TPS_PORTINFO_SINK,
>  	TPS_PORTINFO_SINK_ACCESSORY,
> @@ -88,6 +106,8 @@ struct tps6598x {
>  	struct mutex lock; /* device lock */
>  	u8 i2c_protocol:1;
>  
> +	u8 is_tps25750:1;
> +
>  	struct typec_port *port;
>  	struct typec_partner *partner;
>  	struct usb_pd_identity partner_identity;
> @@ -708,6 +728,203 @@ static int devm_tps6598_psy_register(struct tps6598x *tps)
>  	return PTR_ERR_OR_ZERO(tps->psy);
>  }
>  
> +static int
> +tps25750_write_firmware(struct tps6598x *tps,
> +			u8 bpms_addr, const u8 *data, size_t len)
> +{
> +	struct i2c_client *client = to_i2c_client(tps->dev);
> +	int ret;
> +	u8 slave_addr;
> +	int timeout;
> +
> +	slave_addr = client->addr;
> +	timeout = client->adapter->timeout;
> +
> +	/*
> +	 * binary configuration size is around ~16Kbytes
> +	 * which might take some time to finish writing it
> +	 */
> +	client->adapter->timeout = msecs_to_jiffies(5000);
> +	client->addr = bpms_addr;
> +
> +	ret = regmap_raw_write(tps->regmap, data[0], &data[1], len - 1);
> +
> +	client->addr = slave_addr;
> +	client->adapter->timeout = timeout;
> +
> +	return ret;
> +}
> +
> +static int
> +tps25750_exec_pbms(struct tps6598x *tps, u8 *in_data, size_t in_len)
> +{
> +	int ret;
> +	u8 rc;
> +
> +	ret = tps6598x_exec_cmd(tps, "PBMs", in_len, in_data,
> +				sizeof(rc), &rc, 4000, 0);
> +	if (ret)
> +		return ret;
> +
> +	switch (rc) {
> +	case TPS_TASK_BPMS_INVALID_BUNDLE_SIZE:
> +		dev_err(tps->dev, "%s: invalid fw size\n", __func__);
> +		return -EINVAL;
> +	case TPS_TASK_BPMS_INVALID_SLAVE_ADDR:
> +		dev_err(tps->dev, "%s: invalid slave address\n", __func__);
> +		return -EINVAL;
> +	case TPS_TASK_BPMS_INVALID_TIMEOUT:
> +		dev_err(tps->dev, "%s: timed out\n", __func__);
> +		return -ETIMEDOUT;
> +	default:
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tps25750_abort_patch_process(struct tps6598x *tps)
> +{
> +	int ret;
> +	u8 mode;
> +
> +	ret = tps6598x_exec_cmd(tps, "PBMe", 0, NULL, 0, NULL, 1000, 0);
> +	if (ret)
> +		return ret;
> +
> +	ret = tps6598x_check_mode(tps, &mode);
> +	if (mode != TPS_MODE_PTCH)
> +		dev_err(tps->dev, "failed to switch to \"PTCH\" mode\n");
> +
> +	return ret;
> +}
> +
> +static int tps25750_start_patch_burst_mode(struct tps6598x *tps)
> +{
> +	int ret;
> +	const struct firmware *fw;
> +	const char *firmware_name;
> +	struct {
> +		u32 fw_size;
> +		u8 addr;
> +		u8 timeout;
> +	} __packed bpms_data;
> +
> +	ret = device_property_read_string(tps->dev, "firmware-name",
> +					  &firmware_name);
> +	if (ret)
> +		return ret;
> +
> +	ret = request_firmware(&fw, firmware_name, tps->dev);
> +	if (ret) {
> +		dev_err(tps->dev, "failed to retrieve \"%s\"\n", firmware_name);
> +		return ret;
> +	}
> +
> +	if (fw->size == 0) {
> +		ret = -EINVAL;
> +		goto release_fw;
> +	}
> +
> +	ret = device_property_read_u8(tps->dev, "ti,patch-address", &bpms_data.addr);
> +	if (ret) {
> +		dev_err(tps->dev, "failed to get patch address\n");
> +		return ret;
> +	}
> +
> +	bpms_data.fw_size = fw->size;
> +	bpms_data.timeout = TPS_BUNDLE_TIMEOUT;
> +
> +	ret = tps25750_exec_pbms(tps, (u8 *)&bpms_data, sizeof(bpms_data));
> +	if (ret)
> +		goto release_fw;
> +
> +	ret = tps25750_write_firmware(tps, bpms_data.addr, fw->data, fw->size);
> +	if (ret) {
> +		dev_err(tps->dev, "Failed to write patch %s of %lu bytes\n",
> +			firmware_name, fw->size);
> +		goto release_fw;
> +	}
> +
> +	/*
> +	 * A delay of 500us is required after the firmware is written
> +	 * based on pg.62 in tps6598x Host Interface Technical
> +	 * Reference Manual
> +	 * https://www.ti.com/lit/ug/slvuc05a/slvuc05a.pdf
> +	 */
> +	udelay(500);
> +
> +release_fw:
> +	release_firmware(fw);
> +
> +	return ret;
> +}
> +
> +static int tps25750_complete_patch_process(struct tps6598x *tps)
> +{
> +	int ret;
> +	u8 out_data[40];
> +	u8 dummy[2] = { };
> +
> +	/*
> +	 * Without writing something to DATA_IN, this command would
> +	 * return an error
> +	 */
> +	ret = tps6598x_exec_cmd(tps, "PBMc", sizeof(dummy), dummy,
> +				sizeof(out_data), out_data, 2000, 20);
> +	if (ret)
> +		return ret;
> +
> +	if (out_data[TPS_PBMC_RC]) {
> +		dev_err(tps->dev,
> +			"%s: pbmc failed: %u\n", __func__,
> +			out_data[TPS_PBMC_RC]);
> +		return -EIO;
> +	}
> +
> +	if (out_data[TPS_PBMC_DPCS]) {
> +		dev_err(tps->dev,
> +			"%s: failed device patch complete status: %u\n",
> +			__func__, out_data[TPS_PBMC_DPCS]);
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tps25750_apply_patch(struct tps6598x *tps)
> +{
> +	int ret;
> +	unsigned long timeout;
> +	u8 mode;
> +
> +	ret = tps25750_start_patch_burst_mode(tps);
> +	if (ret) {
> +		tps25750_abort_patch_process(tps);
> +		return ret;
> +	}
> +
> +	ret = tps25750_complete_patch_process(tps);
> +	if (ret)
> +		return ret;
> +
> +	timeout = jiffies + msecs_to_jiffies(1000);
> +
> +	do {
> +		ret = tps6598x_check_mode(tps, &mode);
> +		if (ret)
> +			return ret;
> +
> +		if (time_is_before_jiffies(timeout))
> +			return -ETIMEDOUT;
> +
> +	} while (mode != TPS_MODE_APP);
> +
> +	dev_info(tps->dev, "controller switched to \"APP\" mode\n");
> +
> +	return 0;
> +};
> +
>  static int tps6598x_probe(struct i2c_client *client)
>  {
>  	irq_handler_t irq_handler = tps6598x_interrupt;
> @@ -757,6 +974,8 @@ static int tps6598x_probe(struct i2c_client *client)
>  
>  		irq_handler = cd321x_interrupt;
>  	} else {
> +
> +		tps->is_tps25750 = of_device_is_compatible(np, "ti,tps25750");
>  		/* Enable power status, data status and plug event interrupts */
>  		mask1 = TPS_REG_INT_POWER_STATUS_UPDATE |
>  			TPS_REG_INT_DATA_STATUS_UPDATE |
> @@ -769,9 +988,15 @@ static int tps6598x_probe(struct i2c_client *client)
>  	if (ret)
>  		return ret;
>  
> +	if (tps->is_tps25750 && mode == TPS_MODE_PTCH) {
> +		ret = tps25750_apply_patch(tps);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	ret = tps6598x_write64(tps, TPS_REG_INT_MASK1, mask1);
>  	if (ret)
> -		return ret;
> +		goto err_reset_controller;
>  
>  	ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
>  	if (ret < 0)
> @@ -891,6 +1116,10 @@ static int tps6598x_probe(struct i2c_client *client)
>  	fwnode_handle_put(fwnode);
>  err_clear_mask:
>  	tps6598x_write64(tps, TPS_REG_INT_MASK1, 0);
> +err_reset_controller:
> +	/* Reset PD controller to remove any applied patch */
> +	if (tps->is_tps25750)
> +		tps6598x_exec_cmd(tps, "GAID", 0, NULL, 0, NULL, 2000, 0);
>  	return ret;
>  }
>  
> @@ -901,9 +1130,14 @@ static void tps6598x_remove(struct i2c_client *client)
>  	if (!client->irq)
>  		cancel_delayed_work_sync(&tps->wq_poll);
>  
> +	devm_free_irq(tps->dev, client->irq, tps);
>  	tps6598x_disconnect(tps, 0);
>  	typec_unregister_port(tps->port);
>  	usb_role_switch_put(tps->role_sw);
> +
> +	/* Reset PD controller to remove any applied patch */
> +	if (tps->is_tps25750)
> +		tps6598x_exec_cmd(tps, "GAID", 0, NULL, 0, NULL, 2000, 0);
>  }
>  
>  static int __maybe_unused tps6598x_suspend(struct device *dev)
> @@ -946,6 +1180,7 @@ static const struct dev_pm_ops tps6598x_pm_ops = {
>  static const struct of_device_id tps6598x_of_match[] = {
>  	{ .compatible = "ti,tps6598x", },
>  	{ .compatible = "apple,cd321x", },
> +	{ .compatible = "ti,tps25750", },

This is probable OK for now, we can mix this stuff into core.c now, but
later I want this driver (core.c) to be converted into a library that
contains only the common functionality. TPS5750 will at that point have
its own probe/glue driver.

>  	{}
>  };
>  MODULE_DEVICE_TABLE(of, tps6598x_of_match);
> -- 
> 2.34.1

thanks,

-- 
heikki