diff mbox

Applied "spi: sh-msiof: Add slave mode support" to the spi tree

Message ID E1dEE6q-0001QI-9k@debutante (mailing list archive)
State Not Applicable
Delegated to: Geert Uytterhoeven
Headers show

Commit Message

Mark Brown May 26, 2017, 12:12 p.m. UTC
The patch

   spi: sh-msiof: Add slave mode support

has been applied to the spi tree at

   git://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 cf9e4784f3bde3e4749163384f27450ddffe746c Mon Sep 17 00:00:00 2001
From: Hisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Date: Mon, 22 May 2017 15:11:43 +0200
Subject: [PATCH] spi: sh-msiof: Add slave mode support

Add slave mode support to the MSIOF driver, in both PIO and DMA mode.

For now this only supports the transmission of messages with a size
that is known in advance.

Signed-off-by: Hisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: Timeout handling cleanup, spi core integration, cancellation,
	rewording]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 Documentation/devicetree/bindings/spi/sh-msiof.txt |   2 +
 drivers/spi/spi-sh-msiof.c                         | 111 +++++++++++++++------
 include/linux/spi/sh_msiof.h                       |   6 ++
 3 files changed, 86 insertions(+), 33 deletions(-)
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/spi/sh-msiof.txt b/Documentation/devicetree/bindings/spi/sh-msiof.txt
index dc975064fa27..64ee489571c4 100644
--- a/Documentation/devicetree/bindings/spi/sh-msiof.txt
+++ b/Documentation/devicetree/bindings/spi/sh-msiof.txt
@@ -38,6 +38,8 @@  Optional properties:
 			 specifiers, one for transmission, and one for
 			 reception.
 - dma-names            : Must contain a list of two DMA names, "tx" and "rx".
+- spi-slave            : Empty property indicating the SPI controller is used
+			 in slave mode.
 - renesas,dtdl         : delay sync signal (setup) in transmit mode.
 			 Must contain one of the following values:
 			 0   (no bit delay)
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 2ce15ca97782..c304c7167866 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -2,7 +2,8 @@ 
  * SuperH MSIOF SPI Master Interface
  *
  * Copyright (c) 2009 Magnus Damm
- * Copyright (C) 2014 Glider bvba
+ * Copyright (C) 2014 Renesas Electronics Corporation
+ * Copyright (C) 2014-2017 Glider bvba
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -33,7 +34,6 @@ 
 
 #include <asm/unaligned.h>
 
-
 struct sh_msiof_chipdata {
 	u16 tx_fifo_size;
 	u16 rx_fifo_size;
@@ -53,6 +53,7 @@  struct sh_msiof_spi_priv {
 	void *rx_dma_page;
 	dma_addr_t tx_dma_addr;
 	dma_addr_t rx_dma_addr;
+	bool slave_aborted;
 };
 
 #define TMDR1	0x00	/* Transmit Mode Register 1 */
@@ -337,7 +338,10 @@  static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p,
 	tmp |= !cs_high << MDR1_SYNCAC_SHIFT;
 	tmp |= lsb_first << MDR1_BITLSB_SHIFT;
 	tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p);
-	sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON);
+	if (spi_controller_is_slave(p->master))
+		sh_msiof_write(p, TMDR1, tmp | TMDR1_PCON);
+	else
+		sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON);
 	if (p->master->flags & SPI_MASTER_MUST_TX) {
 		/* These bits are reserved if RX needs TX */
 		tmp &= ~0x0000ffff;
@@ -564,17 +568,19 @@  static int sh_msiof_prepare_message(struct spi_master *master,
 
 static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
 {
-	int ret;
+	bool slave = spi_controller_is_slave(p->master);
+	int ret = 0;
 
 	/* setup clock and rx/tx signals */
-	ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
+	if (!slave)
+		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
 	if (rx_buf && !ret)
 		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
 	if (!ret)
 		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
 
 	/* start by setting frame bit */
-	if (!ret)
+	if (!ret && !slave)
 		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
 
 	return ret;
@@ -582,20 +588,49 @@  static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
 
 static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf)
 {
-	int ret;
+	bool slave = spi_controller_is_slave(p->master);
+	int ret = 0;
 
 	/* shut down frame, rx/tx and clock signals */
-	ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
+	if (!slave)
+		ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
 	if (!ret)
 		ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
 	if (rx_buf && !ret)
 		ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
-	if (!ret)
+	if (!ret && !slave)
 		ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
 
 	return ret;
 }
 
+static int sh_msiof_slave_abort(struct spi_master *master)
+{
+	struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
+
+	p->slave_aborted = true;
+	complete(&p->done);
+	return 0;
+}
+
+static int sh_msiof_wait_for_completion(struct sh_msiof_spi_priv *p)
+{
+	if (spi_controller_is_slave(p->master)) {
+		if (wait_for_completion_interruptible(&p->done) ||
+		    p->slave_aborted) {
+			dev_dbg(&p->pdev->dev, "interrupted\n");
+			return -EINTR;
+		}
+	} else {
+		if (!wait_for_completion_timeout(&p->done, HZ)) {
+			dev_err(&p->pdev->dev, "timeout\n");
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
 static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
 				  void (*tx_fifo)(struct sh_msiof_spi_priv *,
 						  const void *, int, int),
@@ -628,6 +663,7 @@  static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
 		tx_fifo(p, tx_buf, words, fifo_shift);
 
 	reinit_completion(&p->done);
+	p->slave_aborted = false;
 
 	ret = sh_msiof_spi_start(p, rx_buf);
 	if (ret) {
@@ -636,11 +672,9 @@  static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
 	}
 
 	/* wait for tx fifo to be emptied / rx fifo to be filled */
-	if (!wait_for_completion_timeout(&p->done, HZ)) {
-		dev_err(&p->pdev->dev, "PIO timeout\n");
-		ret = -ETIMEDOUT;
+	ret = sh_msiof_wait_for_completion(p);
+	if (ret)
 		goto stop_reset;
-	}
 
 	/* read rx fifo */
 	if (rx_buf)
@@ -732,6 +766,7 @@  static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
 	sh_msiof_write(p, IER, ier_bits);
 
 	reinit_completion(&p->done);
+	p->slave_aborted = false;
 
 	/* Now start DMA */
 	if (rx)
@@ -746,11 +781,9 @@  static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
 	}
 
 	/* wait for tx fifo to be emptied / rx fifo to be filled */
-	if (!wait_for_completion_timeout(&p->done, HZ)) {
-		dev_err(&p->pdev->dev, "DMA timeout\n");
-		ret = -ETIMEDOUT;
+	ret = sh_msiof_wait_for_completion(p);
+	if (ret)
 		goto stop_reset;
-	}
 
 	/* clear status bits */
 	sh_msiof_reset_str(p);
@@ -843,7 +876,8 @@  static int sh_msiof_transfer_one(struct spi_master *master,
 	int ret;
 
 	/* setup clocks (clock already enabled in chipselect()) */
-	sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
+	if (!spi_controller_is_slave(p->master))
+		sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
 
 	while (master->dma_tx && len > 15) {
 		/*
@@ -998,8 +1032,12 @@  static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
 	if (!info)
 		return NULL;
 
+	info->mode = of_property_read_bool(np, "spi-slave") ? MSIOF_SPI_SLAVE
+							    : MSIOF_SPI_MASTER;
+
 	/* Parse the MSIOF properties */
-	of_property_read_u32(np, "num-cs", &num_cs);
+	if (info->mode == MSIOF_SPI_MASTER)
+		of_property_read_u32(np, "num-cs", &num_cs);
 	of_property_read_u32(np, "renesas,tx-fifo-size",
 					&info->tx_fifo_override);
 	of_property_read_u32(np, "renesas,rx-fifo-size",
@@ -1159,34 +1197,40 @@  static int sh_msiof_spi_probe(struct platform_device *pdev)
 	struct spi_master *master;
 	const struct sh_msiof_chipdata *chipdata;
 	const struct of_device_id *of_id;
+	struct sh_msiof_spi_info *info;
 	struct sh_msiof_spi_priv *p;
 	int i;
 	int ret;
 
-	master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
-	if (master == NULL)
-		return -ENOMEM;
-
-	p = spi_master_get_devdata(master);
-
-	platform_set_drvdata(pdev, p);
-	p->master = master;
-
 	of_id = of_match_device(sh_msiof_match, &pdev->dev);
 	if (of_id) {
 		chipdata = of_id->data;
-		p->info = sh_msiof_spi_parse_dt(&pdev->dev);
+		info = sh_msiof_spi_parse_dt(&pdev->dev);
 	} else {
 		chipdata = (const void *)pdev->id_entry->driver_data;
-		p->info = dev_get_platdata(&pdev->dev);
+		info = dev_get_platdata(&pdev->dev);
 	}
 
-	if (!p->info) {
+	if (!info) {
 		dev_err(&pdev->dev, "failed to obtain device info\n");
-		ret = -ENXIO;
-		goto err1;
+		return -ENXIO;
 	}
 
+	if (info->mode == MSIOF_SPI_SLAVE)
+		master = spi_alloc_slave(&pdev->dev,
+					 sizeof(struct sh_msiof_spi_priv));
+	else
+		master = spi_alloc_master(&pdev->dev,
+					  sizeof(struct sh_msiof_spi_priv));
+	if (master == NULL)
+		return -ENOMEM;
+
+	p = spi_master_get_devdata(master);
+
+	platform_set_drvdata(pdev, p);
+	p->master = master;
+	p->info = info;
+
 	init_completion(&p->done);
 
 	p->clk = devm_clk_get(&pdev->dev, NULL);
@@ -1237,6 +1281,7 @@  static int sh_msiof_spi_probe(struct platform_device *pdev)
 	master->num_chipselect = p->info->num_chipselect;
 	master->setup = sh_msiof_spi_setup;
 	master->prepare_message = sh_msiof_prepare_message;
+	master->slave_abort = sh_msiof_slave_abort;
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
 	master->auto_runtime_pm = true;
 	master->transfer_one = sh_msiof_transfer_one;
diff --git a/include/linux/spi/sh_msiof.h b/include/linux/spi/sh_msiof.h
index b087a85f5f72..f74b581f242f 100644
--- a/include/linux/spi/sh_msiof.h
+++ b/include/linux/spi/sh_msiof.h
@@ -1,10 +1,16 @@ 
 #ifndef __SPI_SH_MSIOF_H__
 #define __SPI_SH_MSIOF_H__
 
+enum {
+	MSIOF_SPI_MASTER,
+	MSIOF_SPI_SLAVE,
+};
+
 struct sh_msiof_spi_info {
 	int tx_fifo_override;
 	int rx_fifo_override;
 	u16 num_chipselect;
+	int mode;
 	unsigned int dma_tx_id;
 	unsigned int dma_rx_id;
 	u32 dtdl;