Applied "spi: meson-spicc: enhance output enable feature" to the spi tree

[Mark Brown <broonie@xxxxxxxxxx>]

The patch

   spi: meson-spicc: enhance output enable feature

has been applied to the spi tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From a6cda1f905b4a5442eecce94bda1e136f7e1e539 Mon Sep 17 00:00:00 2001
From: Sunny Luo <sunny.luo@xxxxxxxxxxx>
Date: Thu, 12 Mar 2020 14:31:24 +0100
Subject: [PATCH] spi: meson-spicc: enhance output enable feature

The SPICC controller in Meson-AXG is capable of driving the CLK/MOSI/SS
signal lines through the idle state (between two transmission operation),
which avoid the signals floating in unexpected state.

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Yixun Lan <yixun.lan@xxxxxxxxxxx>
Signed-off-by: Sunny Luo <sunny.luo@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200312133131.26430-3-narmstrong@xxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
 drivers/spi/spi-meson-spicc.c | 53 +++++++++++++++++++++++++++++++++--
 1 file changed, 51 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-meson-spicc.c b/drivers/spi/spi-meson-spicc.c
index 8425e5ae1273..ba70ef94a82a 100644
--- a/drivers/spi/spi-meson-spicc.c
+++ b/drivers/spi/spi-meson-spicc.c
@@ -9,11 +9,13 @@
 
 #include <linux/bitfield.h>
 #include <linux/clk.h>
+#include <linux/clk-provider.h>
 #include <linux/device.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/spi/spi.h>
 #include <linux/types.h>
@@ -113,12 +115,23 @@
 
 #define SPICC_DWADDR	0x24	/* Write Address of DMA */
 
+#define SPICC_ENH_CTL0	0x38	/* Enhanced Feature */
+#define SPICC_ENH_MOSI_OEN		BIT(25)
+#define SPICC_ENH_CLK_OEN		BIT(26)
+#define SPICC_ENH_CS_OEN		BIT(27)
+#define SPICC_ENH_CLK_CS_DELAY_EN	BIT(28)
+#define SPICC_ENH_MAIN_CLK_AO		BIT(29)
+
 #define writel_bits_relaxed(mask, val, addr) \
 	writel_relaxed((readl_relaxed(addr) & ~(mask)) | (val), addr)
 
 #define SPICC_BURST_MAX	16
 #define SPICC_FIFO_HALF 10
 
+struct meson_spicc_data {
+	bool				has_oen;
+};
+
 struct meson_spicc_device {
 	struct spi_master		*master;
 	struct platform_device		*pdev;
@@ -126,6 +139,7 @@ struct meson_spicc_device {
 	struct clk			*core;
 	struct spi_message		*message;
 	struct spi_transfer		*xfer;
+	const struct meson_spicc_data	*data;
 	u8				*tx_buf;
 	u8				*rx_buf;
 	unsigned int			bytes_per_word;
@@ -136,6 +150,19 @@ struct meson_spicc_device {
 	bool				is_last_burst;
 };
 
+static void meson_spicc_oen_enable(struct meson_spicc_device *spicc)
+{
+	u32 conf;
+
+	if (!spicc->data->has_oen)
+		return;
+
+	conf = readl_relaxed(spicc->base + SPICC_ENH_CTL0) |
+		SPICC_ENH_MOSI_OEN | SPICC_ENH_CLK_OEN | SPICC_ENH_CS_OEN;
+
+	writel_relaxed(conf, spicc->base + SPICC_ENH_CTL0);
+}
+
 static inline bool meson_spicc_txfull(struct meson_spicc_device *spicc)
 {
 	return !!FIELD_GET(SPICC_TF,
@@ -489,6 +516,13 @@ static int meson_spicc_probe(struct platform_device *pdev)
 	spicc = spi_master_get_devdata(master);
 	spicc->master = master;
 
+	spicc->data = of_device_get_match_data(&pdev->dev);
+	if (!spicc->data) {
+		dev_err(&pdev->dev, "failed to get match data\n");
+		ret = -EINVAL;
+		goto out_master;
+	}
+
 	spicc->pdev = pdev;
 	platform_set_drvdata(pdev, spicc);
 
@@ -548,6 +582,8 @@ static int meson_spicc_probe(struct platform_device *pdev)
 	else
 		master->max_speed_hz = rate >> 2;
 
+	meson_spicc_oen_enable(spicc);
+
 	ret = devm_spi_register_master(&pdev->dev, master);
 	if (ret) {
 		dev_err(&pdev->dev, "spi master registration failed\n");
@@ -577,9 +613,22 @@ static int meson_spicc_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct meson_spicc_data meson_spicc_gx_data = {
+};
+
+static const struct meson_spicc_data meson_spicc_axg_data = {
+	.has_oen		= true,
+};
+
 static const struct of_device_id meson_spicc_of_match[] = {
-	{ .compatible = "amlogic,meson-gx-spicc", },
-	{ .compatible = "amlogic,meson-axg-spicc", },
+	{
+		.compatible	= "amlogic,meson-gx-spicc",
+		.data		= &meson_spicc_gx_data,
+	},
+	{
+		.compatible = "amlogic,meson-axg-spicc",
+		.data		= &meson_spicc_axg_data,
+	},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, meson_spicc_of_match);
-- 
2.20.1