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From:   Sven Peter <sven@svenpeter.dev>
To:     Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc:     Sven Peter <sven@svenpeter.dev>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        =?UTF-8?q?Guido=20G=C3=BCnther?= <agx@sigxcpu.org>,
        "Bryan O'Donoghue" <bryan.odonoghue@linaro.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        Hector Martin <marcan@marcan.st>,
        Mohamed Mediouni <mohamed.mediouni@caramail.com>,
        Stan Skowronek <stan@corellium.com>,
        Mark Kettenis <mark.kettenis@xs4all.nl>,
        Alexander Graf <graf@amazon.com>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>
Subject: [PATCH v3 4/6] usb: typec: tipd: Add support for Apple CD321X
Date:   Tue, 28 Sep 2021 17:55:00 +0200
Message-Id: <20210928155502.71372-5-sven@svenpeter.dev>
In-Reply-To: <20210928155502.71372-1-sven@svenpeter.dev>
References: <20210928155502.71372-1-sven@svenpeter.dev>
MIME-Version: 1.0
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Precedence: bulk

Apple CD321x chips are a variant of the TI TPS 6598x chips.
The major differences are the changed interrupt numbers and
the concurrent connection to the SMC which we must not disturb.

Signed-off-by: Sven Peter <sven@svenpeter.dev>
---
changes since v2:
  - switched from of_device_get_match_data to of_device_is_compatible
    as suggested by Heikki
  - replace "int ret = 0" with "int ret" in cd321x_interrupt since ret
    doesn't need to be initialized

changes since v1:
  - new commit since Heikki suggested to just add a separate irq handler

 drivers/usb/typec/tipd/core.c     | 63 ++++++++++++++++++++++++++++++-
 drivers/usb/typec/tipd/tps6598x.h |  6 +++
 drivers/usb/typec/tipd/trace.h    | 23 +++++++++++
 3 files changed, 91 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
index e785e4aa2d4b..cc4a154eabcb 100644
--- a/drivers/usb/typec/tipd/core.c
+++ b/drivers/usb/typec/tipd/core.c
@@ -9,6 +9,7 @@
 #include <linux/i2c.h>
 #include <linux/acpi.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/power_supply.h>
 #include <linux/regmap.h>
 #include <linux/interrupt.h>
@@ -461,6 +462,51 @@ static void tps6598x_handle_plug_event(struct tps6598x *tps, u32 status)
 	}
 }
 
+static irqreturn_t cd321x_interrupt(int irq, void *data)
+{
+	struct tps6598x *tps = data;
+	u64 event;
+	u32 status;
+	int ret;
+
+	mutex_lock(&tps->lock);
+
+	ret = tps6598x_read64(tps, TPS_REG_INT_EVENT1, &event);
+	if (ret) {
+		dev_err(tps->dev, "%s: failed to read events\n", __func__);
+		goto err_unlock;
+	}
+	trace_cd321x_irq(event);
+
+	if (!event)
+		goto err_unlock;
+
+	if (!tps6598x_read_status(tps, &status))
+		goto err_clear_ints;
+
+	if (event & APPLE_CD_REG_INT_POWER_STATUS_UPDATE)
+		if (!tps6598x_read_power_status(tps))
+			goto err_clear_ints;
+
+	if (event & APPLE_CD_REG_INT_DATA_STATUS_UPDATE)
+		if (!tps6598x_read_data_status(tps))
+			goto err_clear_ints;
+
+	/* Handle plug insert or removal */
+	if (event & APPLE_CD_REG_INT_PLUG_EVENT)
+		tps6598x_handle_plug_event(tps, status);
+
+err_clear_ints:
+	tps6598x_write64(tps, TPS_REG_INT_CLEAR1, event);
+
+err_unlock:
+	mutex_unlock(&tps->lock);
+
+	if (event)
+		return IRQ_HANDLED;
+	return IRQ_NONE;
+}
+
 static irqreturn_t tps6598x_interrupt(int irq, void *data)
 {
 	struct tps6598x *tps = data;
@@ -620,6 +666,8 @@ static int devm_tps6598_psy_register(struct tps6598x *tps)
 
 static int tps6598x_probe(struct i2c_client *client)
 {
+	irq_handler_t irq_handler = tps6598x_interrupt;
+	struct device_node *np = client->dev.of_node;
 	struct typec_capability typec_cap = { };
 	struct tps6598x *tps;
 	struct fwnode_handle *fwnode;
@@ -658,6 +706,18 @@ static int tps6598x_probe(struct i2c_client *client)
 	if (ret)
 		return ret;
 
+	if (np && of_device_is_compatible(np, "apple,cd321x")) {
+		/* CD321X chips have all interrupts masked initially */
+		ret = tps6598x_write64(tps, TPS_REG_INT_MASK1,
+					APPLE_CD_REG_INT_POWER_STATUS_UPDATE |
+					APPLE_CD_REG_INT_DATA_STATUS_UPDATE |
+					APPLE_CD_REG_INT_PLUG_EVENT);
+		if (ret)
+			return ret;
+
+		irq_handler = cd321x_interrupt;
+	}
+
 	ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
 	if (ret < 0)
 		return ret;
@@ -739,7 +799,7 @@ static int tps6598x_probe(struct i2c_client *client)
 	}
 
 	ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
-					tps6598x_interrupt,
+					irq_handler,
 					IRQF_SHARED | IRQF_ONESHOT,
 					dev_name(&client->dev), tps);
 	if (ret) {
@@ -773,6 +833,7 @@ static int tps6598x_remove(struct i2c_client *client)
 
 static const struct of_device_id tps6598x_of_match[] = {
 	{ .compatible = "ti,tps6598x", },
+	{ .compatible = "apple,cd321x", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, tps6598x_of_match);
diff --git a/drivers/usb/typec/tipd/tps6598x.h b/drivers/usb/typec/tipd/tps6598x.h
index 003a577be216..e13b16419843 100644
--- a/drivers/usb/typec/tipd/tps6598x.h
+++ b/drivers/usb/typec/tipd/tps6598x.h
@@ -129,6 +129,12 @@
 #define TPS_REG_INT_HARD_RESET				BIT(1)
 #define TPS_REG_INT_PD_SOFT_RESET			BIT(0)
 
+/* Apple-specific TPS_REG_INT_* bits */
+#define APPLE_CD_REG_INT_DATA_STATUS_UPDATE		BIT(10)
+#define APPLE_CD_REG_INT_POWER_STATUS_UPDATE		BIT(9)
+#define APPLE_CD_REG_INT_STATUS_UPDATE			BIT(8)
+#define APPLE_CD_REG_INT_PLUG_EVENT			BIT(1)
+
 /* TPS_REG_POWER_STATUS bits */
 #define TPS_POWER_STATUS_CONNECTION(x)  TPS_FIELD_GET(BIT(0), (x))
 #define TPS_POWER_STATUS_SOURCESINK(x)	TPS_FIELD_GET(BIT(1), (x))
diff --git a/drivers/usb/typec/tipd/trace.h b/drivers/usb/typec/tipd/trace.h
index 5d09d6f78930..12cad1bde7cc 100644
--- a/drivers/usb/typec/tipd/trace.h
+++ b/drivers/usb/typec/tipd/trace.h
@@ -67,6 +67,13 @@
 		{ TPS_REG_INT_USER_VID_ALT_MODE_ATTN_VDM,	"USER_VID_ALT_MODE_ATTN_VDM" }, \
 		{ TPS_REG_INT_USER_VID_ALT_MODE_OTHER_VDM,	"USER_VID_ALT_MODE_OTHER_VDM" })
 
+#define show_cd321x_irq_flags(flags) \
+	__print_flags_u64(flags, "|", \
+		{ APPLE_CD_REG_INT_PLUG_EVENT,			"PLUG_EVENT" }, \
+		{ APPLE_CD_REG_INT_POWER_STATUS_UPDATE,		"POWER_STATUS_UPDATE" }, \
+		{ APPLE_CD_REG_INT_DATA_STATUS_UPDATE,		"DATA_STATUS_UPDATE" }, \
+		{ APPLE_CD_REG_INT_STATUS_UPDATE,		"STATUS_UPDATE" })
+
 #define TPS6598X_STATUS_FLAGS_MASK (GENMASK(31, 0) ^ (TPS_STATUS_CONN_STATE_MASK | \
 						      TPS_STATUS_PP_5V0_SWITCH_MASK | \
 						      TPS_STATUS_PP_HV_SWITCH_MASK | \
@@ -207,6 +214,22 @@ TRACE_EVENT(tps6598x_irq,
 		      show_irq_flags(__entry->event2))
 );
 
+TRACE_EVENT(cd321x_irq,
+	    TP_PROTO(u64 event),
+	    TP_ARGS(event),
+
+	    TP_STRUCT__entry(
+			     __field(u64, event)
+			     ),
+
+	    TP_fast_assign(
+			   __entry->event = event;
+			   ),
+
+	    TP_printk("event=%s",
+		      show_cd321x_irq_flags(__entry->event))
+);
+
 TRACE_EVENT(tps6598x_status,
 	    TP_PROTO(u32 status),
 	    TP_ARGS(status),
-- 
2.25.1