From: Hisashi Nakamura <hisashi.nakamura.ak@xxxxxxxxxxx> 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@xxxxxxxxxxx> Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@xxxxxxxxxxx> [geert: Timeout handling cleanup, spi core integration, cancellation, rewording] Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Acked-by: Rob Herring <robh@xxxxxxxxxx> --- v5: - No changes, v4: - Add Acked-by, - Use slave_aborted flag and complete() instead of messing with internal completion and thread state, v3: - Clear TIF_SIGPENDING when interrupted to fix cancellation, - Extract sh_msiof_wait_for_completion(), - Add #include <linux/sched/signal.h>, - Convert to use spi_alloc_slave(), v2: - Document "spi-slave" property in DT bindings, - Use spi_controller_is_slave() helper, - Check for "spi-slave" property instead of "slave" child node, - Replace SPI_MASTER_IS_SLAVE by SPI_CONTROLLER_IS_SLAVE, - Implement cancellation. --- 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 --git a/Documentation/devicetree/bindings/spi/sh-msiof.txt b/Documentation/devicetree/bindings/spi/sh-msiof.txt index dc975064fa273c36..64ee489571c42f88 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 2ce15ca977828668..c304c7167866d2db 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 b087a85f5f72a351..f74b581f242f8c43 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; -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html