[PATCH v1 0/3] mailbox: rockchip: Some cleanups

[PATCH v1 0/3] mailbox: rockchip: Some cleanups

[Uwe Kleine-König]

Hello,

while trying to understand how mailbox drivers work, I used the rockchip
driver as a reference for a working driver. I didn't succeed yet (so
it's unclear to me how the .send_data() callback can assume that data
points to a struct rockchip_mbox_msg).

This patch set is the result of picking up the patch opportunities I
noticed while looking through the driver.

Best regards
Uwe

Uwe Kleine-König (3):
  mailbox: rockchip: Add a prefix for register defines
  mailbox: rockchip: Simplify device variant handling
  mailbox: rockchip: Convert to use dev_err_probe()

 drivers/mailbox/rockchip-mailbox.c | 60 ++++++++++++++----------------
 1 file changed, 27 insertions(+), 33 deletions(-)


base-commit: a8406e6c0b793ce0788019683837c40855b55995
-- 
2.55.0.11.g153666a7d9bb

[PATCH v1 1/3] mailbox: rockchip: Add a prefix for register defines

[Uwe Kleine-König]

From: Uwe Kleine-König <u.kleine-koenig@baylibre.com>

This way the defines don't make the impression to be more generic than
they actually are.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/mailbox/rockchip-mailbox.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/mailbox/rockchip-mailbox.c b/drivers/mailbox/rockchip-mailbox.c
index bc2f9dd798dd..7ebe5f0d0233 100644
--- a/drivers/mailbox/rockchip-mailbox.c
+++ b/drivers/mailbox/rockchip-mailbox.c
@@ -12,15 +12,15 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 
-#define MAILBOX_A2B_INTEN		0x00
-#define MAILBOX_A2B_STATUS		0x04
-#define MAILBOX_A2B_CMD(x)		(0x08 + (x) * 8)
-#define MAILBOX_A2B_DAT(x)		(0x0c + (x) * 8)
+#define ROCKCHIP_MAILBOX_A2B_INTEN		0x00
+#define ROCKCHIP_MAILBOX_A2B_STATUS		0x04
+#define ROCKCHIP_MAILBOX_A2B_CMD(x)		(0x08 + (x) * 8)
+#define ROCKCHIP_MAILBOX_A2B_DAT(x)		(0x0c + (x) * 8)
 
-#define MAILBOX_B2A_INTEN		0x28
-#define MAILBOX_B2A_STATUS		0x2C
-#define MAILBOX_B2A_CMD(x)		(0x30 + (x) * 8)
-#define MAILBOX_B2A_DAT(x)		(0x34 + (x) * 8)
+#define ROCKCHIP_MAILBOX_B2A_INTEN		0x28
+#define ROCKCHIP_MAILBOX_B2A_STATUS		0x2C
+#define ROCKCHIP_MAILBOX_B2A_CMD(x)		(0x30 + (x) * 8)
+#define ROCKCHIP_MAILBOX_B2A_DAT(x)		(0x34 + (x) * 8)
 
 struct rockchip_mbox_msg {
 	u32 cmd;
@@ -68,9 +68,10 @@ static int rockchip_mbox_send_data(struct mbox_chan *chan, void *data)
 
 	mb->chans[chans->idx].msg = msg;
 
-	writel_relaxed(msg->cmd, mb->mbox_base + MAILBOX_A2B_CMD(chans->idx));
+	writel_relaxed(msg->cmd, mb->mbox_base +
+		       ROCKCHIP_MAILBOX_A2B_CMD(chans->idx));
 	writel_relaxed(msg->rx_size, mb->mbox_base +
-		       MAILBOX_A2B_DAT(chans->idx));
+		       ROCKCHIP_MAILBOX_A2B_DAT(chans->idx));
 
 	return 0;
 }
@@ -81,7 +82,7 @@ static int rockchip_mbox_startup(struct mbox_chan *chan)
 
 	/* Enable all B2A interrupts */
 	writel_relaxed((1 << mb->mbox.num_chans) - 1,
-		       mb->mbox_base + MAILBOX_B2A_INTEN);
+		       mb->mbox_base + ROCKCHIP_MAILBOX_B2A_INTEN);
 
 	return 0;
 }
@@ -92,7 +93,7 @@ static void rockchip_mbox_shutdown(struct mbox_chan *chan)
 	struct rockchip_mbox_chan *chans = mb->chans;
 
 	/* Disable all B2A interrupts */
-	writel_relaxed(0, mb->mbox_base + MAILBOX_B2A_INTEN);
+	writel_relaxed(0, mb->mbox_base + ROCKCHIP_MAILBOX_B2A_INTEN);
 
 	mb->chans[chans->idx].msg = NULL;
 }
@@ -107,13 +108,13 @@ static irqreturn_t rockchip_mbox_irq(int irq, void *dev_id)
 {
 	int idx;
 	struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id;
-	u32 status = readl_relaxed(mb->mbox_base + MAILBOX_B2A_STATUS);
+	u32 status = readl_relaxed(mb->mbox_base + ROCKCHIP_MAILBOX_B2A_STATUS);
 
 	for (idx = 0; idx < mb->mbox.num_chans; idx++) {
 		if ((status & (1 << idx)) && (irq == mb->chans[idx].irq)) {
 			/* Clear mbox interrupt */
 			writel_relaxed(1 << idx,
-				       mb->mbox_base + MAILBOX_B2A_STATUS);
+				       mb->mbox_base + ROCKCHIP_MAILBOX_B2A_STATUS);
 			return IRQ_WAKE_THREAD;
 		}
 	}
-- 
2.55.0.11.g153666a7d9bb

[PATCH v1 2/3] mailbox: rockchip: Simplify device variant handling

[Uwe Kleine-König]

From: Uwe Kleine-König <u.kleine-koenig@baylibre.com>

There is only a single device variant. Let's not use multi-device
abstraction for that but hardcode the information relevant for that
single device type.

Bloat-o-meter reports the following size reduction for an ARCH=arm64
build:

	add/remove: 0/1 grow/shrink: 0/1 up/down: 0/-492 (-492)
	Function                                     old     new   delta
	rk3368_drv_data                                4       -      -4
	rockchip_mbox_probe                         2084    1596    -488
	Total: Before=7185, After=6693, chg -6.85%

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/mailbox/rockchip-mailbox.c | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/drivers/mailbox/rockchip-mailbox.c b/drivers/mailbox/rockchip-mailbox.c
index 7ebe5f0d0233..ada2bd419880 100644
--- a/drivers/mailbox/rockchip-mailbox.c
+++ b/drivers/mailbox/rockchip-mailbox.c
@@ -22,15 +22,13 @@
 #define ROCKCHIP_MAILBOX_B2A_CMD(x)		(0x30 + (x) * 8)
 #define ROCKCHIP_MAILBOX_B2A_DAT(x)		(0x34 + (x) * 8)
 
+#define ROCKCHIP_MAILBOX_NUM_CHANS		4
+
 struct rockchip_mbox_msg {
 	u32 cmd;
 	int rx_size;
 };
 
-struct rockchip_mbox_data {
-	int num_chans;
-};
-
 struct rockchip_mbox_chan {
 	int idx;
 	int irq;
@@ -151,20 +149,15 @@ static irqreturn_t rockchip_mbox_isr(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static const struct rockchip_mbox_data rk3368_drv_data = {
-	.num_chans = 4,
-};
-
 static const struct of_device_id rockchip_mbox_of_match[] = {
-	{ .compatible = "rockchip,rk3368-mailbox", .data = &rk3368_drv_data},
-	{ },
+	{ .compatible = "rockchip,rk3368-mailbox" },
+	{ }
 };
 MODULE_DEVICE_TABLE(of, rockchip_mbox_of_match);
 
 static int rockchip_mbox_probe(struct platform_device *pdev)
 {
 	struct rockchip_mbox *mb;
-	const struct rockchip_mbox_data *drv_data;
 	struct resource *res;
 	struct clk *pclk;
 	int ret, irq, i;
@@ -172,13 +165,13 @@ static int rockchip_mbox_probe(struct platform_device *pdev)
 	if (!pdev->dev.of_node)
 		return -ENODEV;
 
-	drv_data = (const struct rockchip_mbox_data *) device_get_match_data(&pdev->dev);
-
-	mb = devm_kzalloc(&pdev->dev, struct_size(mb, chans, drv_data->num_chans), GFP_KERNEL);
+	mb = devm_kzalloc(&pdev->dev,
+			  struct_size(mb, chans, ROCKCHIP_MAILBOX_NUM_CHANS),
+			  GFP_KERNEL);
 	if (!mb)
 		return -ENOMEM;
 
-	mb->mbox.chans = devm_kcalloc(&pdev->dev, drv_data->num_chans,
+	mb->mbox.chans = devm_kcalloc(&pdev->dev, ROCKCHIP_MAILBOX_NUM_CHANS,
 				      sizeof(*mb->mbox.chans), GFP_KERNEL);
 	if (!mb->mbox.chans)
 		return -ENOMEM;
@@ -186,7 +179,7 @@ static int rockchip_mbox_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, mb);
 
 	mb->mbox.dev = &pdev->dev;
-	mb->mbox.num_chans = drv_data->num_chans;
+	mb->mbox.num_chans = ROCKCHIP_MAILBOX_NUM_CHANS;
 	mb->mbox.ops = &rockchip_mbox_chan_ops;
 	mb->mbox.txdone_irq = true;
 
@@ -195,7 +188,7 @@ static int rockchip_mbox_probe(struct platform_device *pdev)
 		return PTR_ERR(mb->mbox_base);
 
 	/* Each channel has two buffers for A2B and B2A */
-	mb->buf_size = (size_t)resource_size(res) / (drv_data->num_chans * 2);
+	mb->buf_size = (size_t)resource_size(res) / (ROCKCHIP_MAILBOX_NUM_CHANS * 2);
 
 	pclk = devm_clk_get_enabled(&pdev->dev, "pclk_mailbox");
 	if (IS_ERR(pclk))
-- 
2.55.0.11.g153666a7d9bb

[PATCH v1 3/3] mailbox: rockchip: Convert to use dev_err_probe()

[Uwe Kleine-König]

From: Uwe Kleine-König <u.kleine-koenig@baylibre.com>

This is more compact in source code and also compiles to smaller code.

Bloat-o-meter reports:

	add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-76 (-76)
	Function                                     old     new   delta
	rockchip_mbox_probe                         1596    1592      -4
	_entry_ptr                                    24      16      -8
	__func__                                      62      42     -20
	_entry                                       132      88     -44
	Total: Before=6693, After=6617, chg -1.14%

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/mailbox/rockchip-mailbox.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mailbox/rockchip-mailbox.c b/drivers/mailbox/rockchip-mailbox.c
index ada2bd419880..790c34a22ec5 100644
--- a/drivers/mailbox/rockchip-mailbox.c
+++ b/drivers/mailbox/rockchip-mailbox.c
@@ -215,9 +215,9 @@ static int rockchip_mbox_probe(struct platform_device *pdev)
 
 	ret = devm_mbox_controller_register(&pdev->dev, &mb->mbox);
 	if (ret < 0)
-		dev_err(&pdev->dev, "Failed to register mailbox: %d\n", ret);
+		return dev_err_probe(&pdev->dev, ret, "Failed to register mailbox\n");
 
-	return ret;
+	return 0;
 }
 
 static struct platform_driver rockchip_mbox_driver = {
-- 
2.55.0.11.g153666a7d9bb