From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752470AbeDCPpA (ORCPT ); Tue, 3 Apr 2018 11:45:00 -0400 Received: from smtp57.i.mail.ru ([217.69.128.37]:43102 "EHLO smtp57.i.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752258AbeDCPo6 (ORCPT ); Tue, 3 Apr 2018 11:44:58 -0400 From: Sergey Suloev To: Mark Brown , Maxime Ripard , Chen-Yu Tsai Cc: linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sergey Suloev Subject: [PATCH v3 3/6] spi: sun6i: restrict transfer length in PIO-mode Date: Tue, 3 Apr 2018 18:44:46 +0300 Message-Id: <20180403154449.2443-4-ssuloev@orpaltech.com> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180403154449.2443-1-ssuloev@orpaltech.com> References: <20180403154449.2443-1-ssuloev@orpaltech.com> Authentication-Results: smtp57.i.mail.ru; auth=pass smtp.auth=ssuloev@orpaltech.com smtp.mailfrom=ssuloev@orpaltech.com X-7FA49CB5: 0D63561A33F958A505A817744D892096840FE9263A247D771AB4854A73F4B921725E5C173C3A84C3A1C30C8AFC676C8B69F971CF7D0B934D6C9A9530EBF72002C4224003CC836476C0CAF46E325F83A50BF2EBBBDD9D6B0F05F538519369F3743B503F486389A921A5CC5B56E945C8DA X-Mailru-Sender: C5364AD02485212F3ACDC11E67D84917604D420E97150EFE699A29BC7B69B943069BFC61DABEEB110841D3AAAB1726C63DDE9B364B0DF289264D2CD8C2503E8C22A194DADEED8EEDCA01A23BA9CD1BE7ED14614B50AE0675 X-Mras: OK Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is no need to handle 3/4 empty interrupt as the maximum supported transfer length in PIO mode is equal to FIFO depth, i.e. 128 bytes for sun6i and 64 bytes for sun8i SoCs. Changes in v3: 1) Restored processing of 3/4 FIFO full interrupt. Signed-off-by: Sergey Suloev --- drivers/spi/spi-sun6i.c | 41 +++++++++++++++++------------------------ 1 file changed, 17 insertions(+), 24 deletions(-) diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c index 78acc1f..c09ad10 100644 --- a/drivers/spi/spi-sun6i.c +++ b/drivers/spi/spi-sun6i.c @@ -207,7 +207,10 @@ static void sun6i_spi_set_cs(struct spi_device *spi, bool enable) static size_t sun6i_spi_max_transfer_size(struct spi_device *spi) { - return SUN6I_MAX_XFER_SIZE - 1; + struct spi_master *master = spi->master; + struct sun6i_spi *sspi = spi_master_get_devdata(master); + + return sspi->fifo_depth; } static int sun6i_spi_prepare_message(struct spi_master *master, @@ -255,8 +258,14 @@ static int sun6i_spi_transfer_one(struct spi_master *master, int ret = 0; u32 reg; - if (tfr->len > SUN6I_MAX_XFER_SIZE) - return -EINVAL; + /* A zero length transfer never finishes if programmed + in the hardware */ + if (!tfr->len) + return 0; + + /* Don't support transfer larger than the FIFO */ + if (tfr->len > sspi->fifo_depth) + return -EMSGSIZE; reinit_completion(&sspi->done); sspi->tx_buf = tfr->tx_buf; @@ -278,8 +287,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master, */ trig_level = sspi->fifo_depth / 4 * 3; sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG, - (trig_level << SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS) | - (trig_level << SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS)); + (trig_level << SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS)); reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); @@ -343,11 +351,8 @@ static int sun6i_spi_transfer_one(struct spi_master *master, sun6i_spi_fill_fifo(sspi, sspi->fifo_depth); /* Enable the interrupts */ - sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, SUN6I_INT_CTL_TC); sun6i_spi_enable_interrupt(sspi, SUN6I_INT_CTL_TC | SUN6I_INT_CTL_RF_RDY); - if (tx_len > sspi->fifo_depth) - sun6i_spi_enable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ); /* Start the transfer */ reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); @@ -376,7 +381,9 @@ out: static irqreturn_t sun6i_spi_handler(int irq, void *dev_id) { struct sun6i_spi *sspi = dev_id; - u32 status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG); + u32 status; + + status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG); /* Transfer complete */ if (status & SUN6I_INT_CTL_TC) { @@ -388,26 +395,12 @@ static irqreturn_t sun6i_spi_handler(int irq, void *dev_id) /* Receive FIFO 3/4 full */ if (status & SUN6I_INT_CTL_RF_RDY) { - sun6i_spi_drain_fifo(sspi, SUN6I_FIFO_DEPTH); + sun6i_spi_drain_fifo(sspi, sspi->fifo_depth); /* Only clear the interrupt _after_ draining the FIFO */ sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_RF_RDY); return IRQ_HANDLED; } - /* Transmit FIFO 3/4 empty */ - if (status & SUN6I_INT_CTL_TF_ERQ) { - sun6i_spi_fill_fifo(sspi, SUN6I_FIFO_DEPTH); - - if (!sspi->len) - /* nothing left to transmit */ - sun6i_spi_disable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ); - - /* Only clear the interrupt _after_ re-seeding the FIFO */ - sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TF_ERQ); - - return IRQ_HANDLED; - } - return IRQ_NONE; } -- 2.16.2