[PATCH 2/2] clk: rs9: Add support for 9FGV0841

[Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>]

This model is similar to 9FGV0441, the DIFx bits start at bit 0 again,
except this chip has 8 outputs. Adjust rs9_calc_dif() to special-case
the 9FGV0241 where DIFx bits start at 1. Extract only vendor ID from
VID register, the top 4 bits are revision ID which are not useful for
the vendor ID check.

Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>
---
Cc: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
Cc: Conor Dooley <conor+dt@xxxxxxxxxx>
Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>
Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-clk@xxxxxxxxxxxxxxx
Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
---
 drivers/clk/clk-renesas-pcie.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/clk-renesas-pcie.c b/drivers/clk/clk-renesas-pcie.c
index 6606aba253c5..f8dd79b18d5a 100644
--- a/drivers/clk/clk-renesas-pcie.c
+++ b/drivers/clk/clk-renesas-pcie.c
@@ -7,6 +7,7 @@
  * Currently supported:
  *   - 9FGV0241
  *   - 9FGV0441
+ *   - 9FGV0841
  *
  * Copyright (C) 2022 Marek Vasut <marex@xxxxxxx>
  */
@@ -42,6 +43,7 @@
 #define RS9_REG_DID				0x6
 #define RS9_REG_BCP				0x7
 
+#define RS9_REG_VID_MASK			GENMASK(3, 0)
 #define RS9_REG_VID_IDT				0x01
 
 #define RS9_REG_DID_TYPE_FGV			(0x0 << RS9_REG_DID_TYPE_SHIFT)
@@ -53,6 +55,7 @@
 enum rs9_model {
 	RENESAS_9FGV0241,
 	RENESAS_9FGV0441,
+	RENESAS_9FGV0841,
 };
 
 /* Structure to describe features of a particular 9-series model */
@@ -162,12 +165,15 @@ static u8 rs9_calc_dif(const struct rs9_driver_data *rs9, int idx)
 {
 	enum rs9_model model = rs9->chip_info->model;
 
+	/*
+	 * On 9FGV0241, the DIF OE0 is BIT(1) and DIF OE(1) is BIT(2),
+	 * on 9FGV0441 and 9FGV0841 the DIF OE0 is BIT(0) and so on.
+	 * Increment the index in the 9FGV0241 special case here.
+	 */
 	if (model == RENESAS_9FGV0241)
-		return BIT(idx + 1);
-	else if (model == RENESAS_9FGV0441)
-		return BIT(idx);
+		idx++;
 
-	return 0;
+	return BIT(idx);
 }
 
 static int rs9_get_output_config(struct rs9_driver_data *rs9, int idx)
@@ -333,6 +339,7 @@ static int rs9_probe(struct i2c_client *client)
 	if (ret < 0)
 		return ret;
 
+	vid &= RS9_REG_VID_MASK;
 	if (vid != RS9_REG_VID_IDT || did != rs9->chip_info->did)
 		return dev_err_probe(&client->dev, -ENODEV,
 				     "Incorrect VID/DID: %#02x, %#02x. Expected %#02x, %#02x\n",
@@ -391,9 +398,16 @@ static const struct rs9_chip_info renesas_9fgv0441_info = {
 	.did		= RS9_REG_DID_TYPE_FGV | 0x04,
 };
 
+static const struct rs9_chip_info renesas_9fgv0841_info = {
+	.model		= RENESAS_9FGV0841,
+	.num_clks	= 8,
+	.did		= RS9_REG_DID_TYPE_FGV | 0x08,
+};
+
 static const struct i2c_device_id rs9_id[] = {
 	{ "9fgv0241", .driver_data = (kernel_ulong_t)&renesas_9fgv0241_info },
 	{ "9fgv0441", .driver_data = (kernel_ulong_t)&renesas_9fgv0441_info },
+	{ "9fgv0841", .driver_data = (kernel_ulong_t)&renesas_9fgv0841_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, rs9_id);
@@ -401,6 +415,7 @@ MODULE_DEVICE_TABLE(i2c, rs9_id);
 static const struct of_device_id clk_rs9_of_match[] = {
 	{ .compatible = "renesas,9fgv0241", .data = &renesas_9fgv0241_info },
 	{ .compatible = "renesas,9fgv0441", .data = &renesas_9fgv0441_info },
+	{ .compatible = "renesas,9fgv0841", .data = &renesas_9fgv0841_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, clk_rs9_of_match);
-- 
2.42.0