[PATCH 2/3] spi: tegra210-quad: Add wait polling support

From: Krishna Yarlagadda <kyarlagadda@nvidia.com>
To: <broonie@kernel.org>, <thierry.reding@gmail.com>,
	<jonathanh@nvidia.com>, <linux-spi@vger.kernel.org>,
	<linux-tegra@vger.kernel.org>, <ashishsingha@nvidia.com>
Cc: <skomatineni@nvidia.com>, <ldewangan@nvidia.com>,
	<robh+dt@kernel.org>, <devicetree@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	"Krishna Yarlagadda" <kyarlagadda@nvidia.com>
Subject: [PATCH 2/3] spi: tegra210-quad: Add wait polling support
Date: Thu, 17 Mar 2022 06:50:05 +0530	[thread overview]
Message-ID: <20220317012006.15080-3-kyarlagadda@nvidia.com> (raw)
In-Reply-To: <20220317012006.15080-1-kyarlagadda@nvidia.com>

Controller can poll for wait state inserted by TPM device and
handle it.

Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
---
 drivers/spi/spi-tegra210-quad.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c
index a2e225e8f7f0..ecf171bfcdce 100644
--- a/drivers/spi/spi-tegra210-quad.c
+++ b/drivers/spi/spi-tegra210-quad.c
@@ -142,6 +142,7 @@
 
 #define QSPI_GLOBAL_CONFIG			0X1a4
 #define QSPI_CMB_SEQ_EN				BIT(0)
+#define QSPI_TPM_WAIT_POLL_EN			BIT(1)
 
 #define QSPI_CMB_SEQ_ADDR			0x1a8
 #define QSPI_ADDRESS_VALUE_SET(X)		(((x) & 0xFFFF) << 0)
@@ -165,11 +166,13 @@ struct tegra_qspi_soc_data {
 	bool has_dma;
 	bool cmb_xfer_capable;
 	bool cs_count;
+	bool has_wait_polling;
 };
 
 struct tegra_qspi_client_data {
 	int tx_clk_tap_delay;
 	int rx_clk_tap_delay;
+	bool wait_polling;
 };
 
 struct tegra_qspi {
@@ -833,6 +836,11 @@ static u32 tegra_qspi_setup_transfer_one(struct spi_device *spi, struct spi_tran
 		else
 			command1 |= QSPI_CONTROL_MODE_0;
 
+		if (tqspi->soc_data->cmb_xfer_capable)
+			command1 &= ~QSPI_CS_SW_HW;
+		else
+			command1 |= QSPI_CS_SW_HW;
+
 		if (spi->mode & SPI_CS_HIGH)
 			command1 |= QSPI_CS_SW_VAL;
 		else
@@ -917,6 +925,7 @@ static int tegra_qspi_start_transfer_one(struct spi_device *spi,
 
 static struct tegra_qspi_client_data *tegra_qspi_parse_cdata_dt(struct spi_device *spi)
 {
+	struct tegra_qspi *tqspi = spi_master_get_devdata(spi->master);
 	struct tegra_qspi_client_data *cdata;
 
 	cdata = devm_kzalloc(&spi->dev, sizeof(*cdata), GFP_KERNEL);
@@ -927,6 +936,11 @@ static struct tegra_qspi_client_data *tegra_qspi_parse_cdata_dt(struct spi_devic
 				 &cdata->tx_clk_tap_delay);
 	device_property_read_u32(&spi->dev, "nvidia,rx-clk-tap-delay",
 				 &cdata->rx_clk_tap_delay);
+	if (tqspi->soc_data->has_wait_polling)
+		cdata->wait_polling = device_property_read_bool
+					(&spi->dev,
+					 "nvidia,wait-polling");
+
 
 	return cdata;
 }
@@ -1049,6 +1063,7 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 	bool is_first_msg = true;
 	struct spi_transfer *xfer;
 	struct spi_device *spi = msg->spi;
+	struct tegra_qspi_client_data *cdata = spi->controller_data;
 	u8 transfer_phase = 0;
 	u32 cmd1 = 0, dma_ctl = 0;
 	int ret = 0;
@@ -1059,6 +1074,10 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 	/* Enable Combined sequence mode */
 	val = tegra_qspi_readl(tqspi, QSPI_GLOBAL_CONFIG);
 	val |= QSPI_CMB_SEQ_EN;
+	if (cdata->wait_polling)
+		val |= QSPI_TPM_WAIT_POLL_EN;
+	else
+		val &= ~QSPI_TPM_WAIT_POLL_EN;
 	tegra_qspi_writel(tqspi, val, QSPI_GLOBAL_CONFIG);
 	/* Process individual transfer list */
 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
@@ -1158,6 +1177,8 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 		transfer_phase++;
 	}
 
+	ret = 0;
+
 exit:
 	msg->status = ret;
 
@@ -1180,6 +1201,7 @@ static int tegra_qspi_non_combined_seq_xfer(struct tegra_qspi *tqspi,
 	/* Disable Combined sequence mode */
 	val = tegra_qspi_readl(tqspi, QSPI_GLOBAL_CONFIG);
 	val &= ~QSPI_CMB_SEQ_EN;
+	val &= ~QSPI_TPM_WAIT_POLL_EN;
 	tegra_qspi_writel(tqspi, val, QSPI_GLOBAL_CONFIG);
 	list_for_each_entry(transfer, &msg->transfers, transfer_list) {
 		struct spi_transfer *xfer = transfer;
@@ -1439,24 +1461,28 @@ static struct tegra_qspi_soc_data tegra210_qspi_soc_data = {
 	.has_dma = true,
 	.cmb_xfer_capable = false,
 	.cs_count = 1,
+	.has_wait_polling = false,
 };
 
 static struct tegra_qspi_soc_data tegra186_qspi_soc_data = {
 	.has_dma = true,
 	.cmb_xfer_capable = true,
 	.cs_count = 1,
+	.has_wait_polling = false,
 };
 
 static struct tegra_qspi_soc_data tegra234_qspi_soc_data = {
 	.has_dma = false,
 	.cmb_xfer_capable = true,
 	.cs_count = 1,
+	.has_wait_polling = true,
 };
 
 static struct tegra_qspi_soc_data tegra_grace_qspi_soc_data = {
 	.has_dma = false,
 	.cmb_xfer_capable = true,
 	.cs_count = 4,
+	.has_wait_polling = true,
 };
 
 static const struct of_device_id tegra_qspi_of_match[] = {
@@ -1509,6 +1535,7 @@ static int tegra_qspi_probe(struct platform_device *pdev)
 	struct resource		*r;
 	int ret, qspi_irq;
 	int bus_num;
+	u8 val = 0;
 
 	master = devm_spi_alloc_master(&pdev->dev, sizeof(*tqspi));
 	if (!master)
@@ -1585,6 +1612,10 @@ static int tegra_qspi_probe(struct platform_device *pdev)
 	tqspi->spi_cs_timing1 = tegra_qspi_readl(tqspi, QSPI_CS_TIMING1);
 	tqspi->spi_cs_timing2 = tegra_qspi_readl(tqspi, QSPI_CS_TIMING2);
 	tqspi->def_command2_reg = tegra_qspi_readl(tqspi, QSPI_COMMAND2);
+	val = tegra_qspi_readl(tqspi, QSPI_GLOBAL_CONFIG);
+	val &= ~QSPI_CMB_SEQ_EN;
+	val &= ~QSPI_TPM_WAIT_POLL_EN;
+	tegra_qspi_writel(tqspi, val, QSPI_GLOBAL_CONFIG);
 
 	pm_runtime_put(&pdev->dev);
 
-- 
2.17.1

