Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752140AbbFFH0q (ORCPT ); Sat, 6 Jun 2015 03:26:46 -0400 Received: from mail-ie0-f173.google.com ([209.85.223.173]:34452 "EHLO mail-ie0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750829AbbFFH0g (ORCPT ); Sat, 6 Jun 2015 03:26:36 -0400 MIME-Version: 1.0 In-Reply-To: <1433509653-15142-2-git-send-email-ranjit.waghmode@xilinx.com> References: <1433509653-15142-1-git-send-email-ranjit.waghmode@xilinx.com> <1433509653-15142-2-git-send-email-ranjit.waghmode@xilinx.com> Date: Sat, 6 Jun 2015 12:56:35 +0530 Message-ID: Subject: Re: [LINUX RFC V2 2/2] spi: Add support for Zynq Ultrascale+ MPSoC GQSPI controller From: Shubhrajyoti Datta To: Ranjit Waghmode Cc: robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, Kumar Gala , Michal Simek , =?UTF-8?Q?S=C3=B6ren_Brinkmann?= , Mark Brown , devicetree@vger.kernel.org, harinik@xilinx.com, Linux Kernel Mailing List , linux-spi@vger.kernel.org, punnaia@xilinx.com, ran27jit@gmail.com, "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 28753 Lines: 752 hi, Some minor comments. On Fri, Jun 5, 2015 at 6:37 PM, Ranjit Waghmode wrote: > This patch adds support for GQSPI controller driver used by > Zynq Ultrascale+ MPSoC > > Signed-off-by: Ranjit Waghmode > --- > Here is the v2 series. > + */ > +static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high) > +{ > + struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master); > + u32 genfifoentry = 0x0, statusreg, timeout; > + > + genfifoentry |= GQSPI_GENFIFO_MODE_SPI; > + genfifoentry |= xqspi->genfifobus; > + > + if (!is_high) { > + genfifoentry |= xqspi->genfifocs; > + genfifoentry |= GQSPI_GENFIFO_CS_SETUP; > + } else { > + genfifoentry |= GQSPI_GENFIFO_CS_HOLD; > + } > + > + zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry); > + > + /* Dummy generic FIFO entry */ > + zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0); > + > + /* Manually start the generic FIFO command */ > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, > + zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) | > + GQSPI_CFG_START_GEN_FIFO_MASK); > + timeout = 10000; > + /* Wait until the generic FIFO command is empty */ > + do { > + statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST); > + timeout--; Can this be not busy. > + } while (!(statusreg & > + GQSPI_ISR_GENFIFOEMPTY_MASK) && > + (statusreg & GQSPI_ISR_TXEMPTY_MASK) && timeout); > + if (!timeout) > + dev_err(xqspi->dev, "Chip select timed out\n"); > +} > + > +/** > + * zynqmp_qspi_setup_transfer: Configure QSPI controller for specified > + * transfer > + * @qspi: Pointer to the spi_device structure > + * @transfer: Pointer to the spi_transfer structure which provides > + * information about next transfer setup parameters > + * > + * Sets the operational mode of QSPI controller for the next QSPI transfer and > + * sets the requested clock frequency. > + * > + * Return: Always 0 > + * > + * Note: > + * If the requested frequency is not an exact match with what can be > + * obtained using the pre-scalar value, the driver sets the clock > + * frequency which is lower than the requested frequency (maximum lower) > + * for the transfer. > + * > + * If the requested frequency is higher or lower than that is supported > + * by the QSPI controller the driver will set the highest or lowest > + * frequency supported by controller. > + */ > +static int zynqmp_qspi_setup_transfer(struct spi_device *qspi, > + struct spi_transfer *transfer) > +{ > + struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master); > + ulong clk_rate; > + u32 config_reg, req_hz, baud_rate_val = 0; > + > + if (transfer) > + req_hz = transfer->speed_hz; > + else > + req_hz = qspi->max_speed_hz; > + > + /* Set the clock frequency */ > + /* If req_hz == 0, default to lowest speed */ > + clk_rate = clk_get_rate(xqspi->refclk); > + > + while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) && > + (clk_rate / > + (GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz) > + baud_rate_val++; > + > + config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST); > + > + /* Set the QSPI clock phase and clock polarity */ > + config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK); > + > + if (qspi->mode & SPI_CPHA) > + config_reg |= GQSPI_CFG_CLK_PHA_MASK; > + if (qspi->mode & SPI_CPOL) > + config_reg |= GQSPI_CFG_CLK_POL_MASK; > + > + config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK; > + config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT); > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg); > + return 0; > +} > + > +/** > + * zynqmp_qspi_setup: Configure the QSPI controller > + * @qspi: Pointer to the spi_device structure > + * > + * Sets the operational mode of QSPI controller for the next QSPI transfer, > + * baud rate and divisor value to setup the requested qspi clock. > + * > + * Return: 0 Always doesnt seem to be true > + */ > +static int zynqmp_qspi_setup(struct spi_device *qspi) > +{ > + if (qspi->master->busy) > + return -EBUSY; > + return 0; > +} > + > +/** > + * zynqmp_qspi_filltxfifo: Fills the TX FIFO as long as there is room in > + * the FIFO or the bytes required to be > + * transmitted. > + * @xqspi: Pointer to the zynqmp_qspi structure > + * @size: Number of bytes to be copied from TX buffer to TX FIFO > + */ > +static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size) > +{ > + u32 count = 0, intermediate; > + > + while ((xqspi->bytes_to_transfer > 0) && (count < size)) { > + memcpy(&intermediate, xqspi->txbuf, 4); > + zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate); > + > + if (xqspi->bytes_to_transfer >= 4) { > + xqspi->txbuf += 4; > + xqspi->bytes_to_transfer -= 4; > + } else { > + xqspi->txbuf += xqspi->bytes_to_transfer; > + xqspi->bytes_to_transfer = 0; > + } > + count++; > + } > +} > + > +/** > + * zynqmp_qspi_readrxfifo: Fills the RX FIFO as long as there is room in > + * the FIFO. > + * @xqspi: Pointer to the zynqmp_qspi structure > + * @size: Number of bytes to be copied from RX buffer to RX FIFO > + */ > +static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size) > +{ > + ulong data; > + int count = 0; > + > + while ((count < size) && (xqspi->bytes_to_receive > 0)) { > + if (xqspi->bytes_to_receive >= 4) { > + (*(u32 *) xqspi->rxbuf) = > + zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST); > + xqspi->rxbuf += 4; > + xqspi->bytes_to_receive -= 4; > + count += 4; > + } else { > + data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST); > + count += xqspi->bytes_to_receive; > + zynqmp_qspi_copy_read_data(xqspi, data, > + xqspi->bytes_to_receive); > + xqspi->bytes_to_receive = 0; > + } > + } > +} > + > +/** > + * zynqmp_process_dma_irq: Handler for DMA done interrupt of QSPI > + * controller > + * @xqspi: zynqmp_qspi instance pointer > + * > + * This function handles DMA interrupt only. > + */ > +static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi) > +{ > + u32 config_reg, genfifoentry; > + > + dma_unmap_single(xqspi->dev, xqspi->dma_addr, > + xqspi->dma_rx_bytes, DMA_FROM_DEVICE); > + xqspi->rxbuf += xqspi->dma_rx_bytes; > + xqspi->bytes_to_receive -= xqspi->dma_rx_bytes; > + xqspi->dma_rx_bytes = 0; > + > + /* Disabling the DMA interrupts */ why? > + zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST, > + GQSPI_QSPIDMA_DST_I_EN_DONE_MASK); > + > + if (xqspi->bytes_to_receive > 0) { > + /* Switch to IO mode,for remaining bytes to receive */ > + config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST); > + config_reg &= ~GQSPI_CFG_MODE_EN_MASK; > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg); > + > + /* Initiate the transfer of remaining bytes */ > + genfifoentry = xqspi->genfifoentry; > + genfifoentry |= xqspi->bytes_to_receive; > + zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry); > + > + /* Dummy generic FIFO entry */ > + zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0); > + > + /* Manual start */ > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, > + (zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) | > + GQSPI_CFG_START_GEN_FIFO_MASK)); > + > + /* Enable the RX interrupts for IO mode */ > + zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST, > + GQSPI_IER_GENFIFOEMPTY_MASK | > + GQSPI_IER_RXNEMPTY_MASK | > + GQSPI_IER_RXEMPTY_MASK); > + } > +} > + > +/** > + * zynqmp_qspi_irq: Interrupt service routine of the QSPI controller > + * @irq: IRQ number > + * @dev_id: Pointer to the xqspi structure > + * > + * This function handles TX empty only. > + * On TX empty interrupt this function reads the received data from RX FIFO > + * and fills the TX FIFO if there is any data remaining to be transferred. > + * > + * Return: IRQ_HANDLED when interrupt is handled > + * IRQ_NONE otherwise. > + */ > +static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id) > +{ > + struct spi_master *master = dev_id; > + struct zynqmp_qspi *xqspi = spi_master_get_devdata(master); > + int ret = IRQ_NONE; > + u32 status, mask, dma_status = 0; > + > + status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST); > + zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status); > + mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST))); > + > + /* Read and clear DMA status */ > + if (xqspi->mode == GQSPI_MODE_DMA) { > + dma_status = > + zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST); > + zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST, > + dma_status); > + } > + > + if (mask & GQSPI_ISR_TXNOT_FULL_MASK) { > + zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL); > + ret = IRQ_HANDLED; > + } > + > + if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) { > + zynqmp_process_dma_irq(xqspi); > + ret = IRQ_HANDLED; > + } else if (!(mask & GQSPI_IER_RXEMPTY_MASK) && > + (mask & GQSPI_IER_GENFIFOEMPTY_MASK)) { > + zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL); > + ret = IRQ_HANDLED; > + } > + > + if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0) > + && ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) { > + zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK); > + spi_finalize_current_transfer(master); > + ret = IRQ_HANDLED; > + } > + return ret; > +} > + > +/** > + * zynqmp_qspi_selectspimode: Selects SPI mode - x1 or x2 or x4. > + * @xqspi: xqspi is a pointer to the GQSPI instance > + * @spimode: spimode - SPI or DUAL or QUAD. > + * Return: Mask to set desired SPI mode in GENFIFO entry. > + */ > +static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi, > + u8 spimode) > +{ > + u32 mask = 0; > + > + switch (spimode) { > + case GQSPI_SELECT_MODE_DUALSPI: > + mask = GQSPI_GENFIFO_MODE_DUALSPI; > + break; > + case GQSPI_SELECT_MODE_QUADSPI: > + mask = GQSPI_GENFIFO_MODE_QUADSPI; > + break; > + case GQSPI_SELECT_MODE_SPI: > + mask = GQSPI_GENFIFO_MODE_SPI; > + break; > + default: > + dev_warn(xqspi->dev, "Invalid SPI mode\n"); > + } > + > + return mask; > +} > + > +/** > + * zynq_qspi_setuprxdma: This function sets up the RX DMA operation > + * @xqspi: xqspi is a pointer to the GQSPI instance. > + */ > +static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi) > +{ > + u32 rx_bytes, rx_rem, config_reg; > + dma_addr_t addr; > + u64 dma_align = (u64)(uintptr_t)xqspi->rxbuf; > + > + if ((xqspi->bytes_to_receive < 8) || > + ((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) { > + /* Setting to IO mode */ > + config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST); > + config_reg &= ~GQSPI_CFG_MODE_EN_MASK; > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg); > + xqspi->mode = GQSPI_MODE_IO; > + xqspi->dma_rx_bytes = 0; > + return; > + } > + > + rx_rem = xqspi->bytes_to_receive % 4; > + rx_bytes = (xqspi->bytes_to_receive - rx_rem); > + > + addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf, > + rx_bytes, DMA_FROM_DEVICE); > + if (dma_mapping_error(xqspi->dev, addr)) > + dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n"); > + > + xqspi->dma_rx_bytes = rx_bytes; > + xqspi->dma_addr = addr; > + zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST, > + (u32)(addr & 0xffffffff)); > + addr = ((addr >> 16) >> 16); > + zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST, > + ((u32)addr) & 0xfff); > + > + /* Enabling the DMA mode */ > + config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST); > + config_reg &= ~GQSPI_CFG_MODE_EN_MASK; > + config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK; > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg); > + > + /* Switch to DMA mode */ > + xqspi->mode = GQSPI_MODE_DMA; > + > + /* Write the number of bytes to transfer */ > + zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes); > +} > + > +/** > + * zynqmp_qspi_txrxsetup: This function checks the TX/RX buffers in > + * the transfer and sets up the GENFIFO entries, > + * TX FIFO as required. > + * @xqspi: xqspi is a pointer to the GQSPI instance. > + * @transfer: It is a pointer to the structure containing transfer data. > + * @genfifoentry: genfifoentry is pointer to the variable in which > + * GENFIFO mask is returned to calling function > + */ > +static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi, > + struct spi_transfer *transfer, > + u32 *genfifoentry) > +{ > + u32 config_reg; > + > + /* Transmit */ > + if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) { > + /* Setup data to be TXed */ > + *genfifoentry &= ~GQSPI_GENFIFO_RX; > + *genfifoentry |= GQSPI_GENFIFO_DATA_XFER; > + *genfifoentry |= GQSPI_GENFIFO_TX; > + *genfifoentry |= > + zynqmp_qspi_selectspimode(xqspi, transfer->tx_nbits); > + xqspi->bytes_to_transfer = transfer->len; > + if (xqspi->mode == GQSPI_MODE_DMA) { > + config_reg = zynqmp_gqspi_read(xqspi, > + GQSPI_CONFIG_OFST); > + config_reg &= ~GQSPI_CFG_MODE_EN_MASK; > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, > + config_reg); > + xqspi->mode = GQSPI_MODE_IO; > + } > + zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH); > + /* Discard RX data */ > + xqspi->bytes_to_receive = 0; > + } else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) { > + /* Receive */ > + > + /* TX auto fill */ > + *genfifoentry &= ~GQSPI_GENFIFO_TX; > + /* Setup RX */ > + *genfifoentry |= GQSPI_GENFIFO_DATA_XFER; > + *genfifoentry |= GQSPI_GENFIFO_RX; > + *genfifoentry |= > + zynqmp_qspi_selectspimode(xqspi, transfer->rx_nbits); > + xqspi->bytes_to_transfer = 0; > + xqspi->bytes_to_receive = transfer->len; > + zynq_qspi_setuprxdma(xqspi); > + } Not a comment rather a query what happens in case of both rx and tx. > +} > + > +/** > + * zynqmp_qspi_start_transfer: Initiates the QSPI transfer > + * @master: Pointer to the spi_master structure which provides > + * information about the controller. > + * @qspi: Pointer to the spi_device structure > + * @transfer: Pointer to the spi_transfer structure which provide information > + * about next transfer parameters > + * > + * This function fills the TX FIFO, starts the QSPI transfer, and waits for the > + * transfer to be completed. > + * > + * Return: Number of bytes transferred in the last transfer > + */ > +static int zynqmp_qspi_start_transfer(struct spi_master *master, > + struct spi_device *qspi, > + struct spi_transfer *transfer) > +{ > + struct zynqmp_qspi *xqspi = spi_master_get_devdata(master); > + u32 genfifoentry = 0x0, transfer_len; > + > + xqspi->txbuf = transfer->tx_buf; > + xqspi->rxbuf = transfer->rx_buf; > + > + zynqmp_qspi_setup_transfer(qspi, transfer); > + > + genfifoentry |= xqspi->genfifocs; > + genfifoentry |= xqspi->genfifobus; > + > + zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry); > + > + if (xqspi->mode == GQSPI_MODE_DMA) > + transfer_len = xqspi->dma_rx_bytes; > + else > + transfer_len = transfer->len; > + > + xqspi->genfifoentry = genfifoentry; > + if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) { > + genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK; > + genfifoentry |= transfer_len; > + zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry); > + } else { > + int tempcount = transfer_len; > + u32 exponent = 8; /* 2^8 = 256 */ > + u8 imm_data = tempcount & 0xFF; > + > + tempcount &= ~(tempcount & 0xFF); > + /* Immediate entry */ > + if (tempcount != 0) { > + /* Exponent entries */ > + genfifoentry |= GQSPI_GENFIFO_EXP; > + while (tempcount != 0) { > + if (tempcount & GQSPI_GENFIFO_EXP_START) { > + genfifoentry &= > + ~GQSPI_GENFIFO_IMM_DATA_MASK; > + genfifoentry |= exponent; > + zynqmp_gqspi_write(xqspi, > + GQSPI_GEN_FIFO_OFST, > + genfifoentry); > + } > + tempcount = tempcount >> 1; > + exponent++; > + } > + } > + if (imm_data != 0) { > + genfifoentry &= ~GQSPI_GENFIFO_EXP; > + genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK; > + genfifoentry |= (u8) (imm_data & 0xFF); > + zynqmp_gqspi_write(xqspi, > + GQSPI_GEN_FIFO_OFST, genfifoentry); > + } > + } > + > + if ((xqspi->mode == GQSPI_MODE_IO) && > + (xqspi->rxbuf != NULL)) { > + /* Dummy generic FIFO entry */ > + zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0); > + } > + > + /* Since we are using manual mode */ > + zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, > + zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) | > + GQSPI_CFG_START_GEN_FIFO_MASK); > + > + if (xqspi->txbuf != NULL) > + /* Enable interrupts for TX */ > + zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST, > + GQSPI_IER_TXEMPTY_MASK | > + GQSPI_IER_GENFIFOEMPTY_MASK | > + GQSPI_IER_TXNOT_FULL_MASK); > + > + if (xqspi->rxbuf != NULL) { > + /* Enable interrupts for RX */ > + if (xqspi->mode == GQSPI_MODE_DMA) { > + /* Enable DMA interrupts */ > + zynqmp_gqspi_write(xqspi, > + GQSPI_QSPIDMA_DST_I_EN_OFST, > + GQSPI_QSPIDMA_DST_I_EN_DONE_MASK); > + } else { > + zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST, > + GQSPI_IER_GENFIFOEMPTY_MASK | > + GQSPI_IER_RXNEMPTY_MASK | > + GQSPI_IER_RXEMPTY_MASK); > + } > + } > + > + return transfer->len; > +} > + > +/** > + * zynqmp_qspi_suspend: Suspend method for the QSPI driver > + * @_dev: Address of the platform_device structure > + * > + * This function stops the QSPI driver queue and disables the QSPI controller > + * > + * Return: Always 0 > + */ > +static int __maybe_unused zynqmp_qspi_suspend(struct device *dev) > +{ > + struct platform_device *pdev = container_of(dev, > + struct platform_device, > + dev); > + struct spi_master *master = platform_get_drvdata(pdev); > + > + spi_master_suspend(master); > + > + zynqmp_unprepare_transfer_hardware(master); > + > + return 0; > +} > + > +/** > + * zynqmp_qspi_resume: Resume method for the QSPI driver > + * @dev: Address of the platform_device structure > + * > + * The function starts the QSPI driver queue and initializes the QSPI > + * controller > + * > + * Return: 0 on success and error value on error > + */ > +static int __maybe_unused zynqmp_qspi_resume(struct device *dev) > +{ > + struct platform_device *pdev = container_of(dev, > + struct platform_device, > + dev); > + struct spi_master *master = platform_get_drvdata(pdev); > + struct zynqmp_qspi *xqspi = spi_master_get_devdata(master); > + int ret = 0; is the initialisation required > + > + ret = clk_enable(xqspi->pclk); > + if (ret) { > + dev_err(dev, "Cannot enable APB clock.\n"); > + return ret; > + } > + > + ret = clk_enable(xqspi->refclk); > + if (ret) { > + dev_err(dev, "Cannot enable device clock.\n"); > + clk_disable(xqspi->pclk); > + return ret; > + } > + > + spi_master_resume(master); > + > + return 0; > +} > + > +static SIMPLE_DEV_PM_OPS(zynqmp_qspi_dev_pm_ops, zynqmp_qspi_suspend, > + zynqmp_qspi_resume); > + > +/** > + * zynqmp_qspi_probe: Probe method for the QSPI driver > + * @pdev: Pointer to the platform_device structure > + * > + * This function initializes the driver data structures and the hardware. > + * > + * Return: 0 on success and error value on failure > + */ > +static int zynqmp_qspi_probe(struct platform_device *pdev) > +{ > + int ret = 0; > + struct spi_master *master; > + struct zynqmp_qspi *xqspi; > + struct resource *res; > + struct device *dev = &pdev->dev; > + > + master = spi_alloc_master(&pdev->dev, sizeof(*xqspi)); > + if (!master) > + return -ENOMEM; > + > + xqspi = spi_master_get_devdata(master); > + master->dev.of_node = pdev->dev.of_node; > + platform_set_drvdata(pdev, master); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + xqspi->regs = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(xqspi->regs)) { > + ret = PTR_ERR(xqspi->regs); > + goto remove_master; > + } > + > + xqspi->dev = dev; > + xqspi->pclk = devm_clk_get(&pdev->dev, "pclk"); > + if (IS_ERR(xqspi->pclk)) { > + dev_err(dev, "pclk clock not found.\n"); > + ret = PTR_ERR(xqspi->pclk); > + goto remove_master; > + } > + > + xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk"); > + if (IS_ERR(xqspi->refclk)) { > + dev_err(dev, "ref_clk clock not found.\n"); > + ret = PTR_ERR(xqspi->refclk); > + goto remove_master; > + } > + > + ret = clk_prepare_enable(xqspi->pclk); > + if (ret) { > + dev_err(dev, "Unable to enable APB clock.\n"); > + goto remove_master; > + } > + > + ret = clk_prepare_enable(xqspi->refclk); > + if (ret) { > + dev_err(dev, "Unable to enable device clock.\n"); > + goto clk_dis_pclk; > + } > + > + /* QSPI controller initializations */ > + zynqmp_qspi_init_hw(xqspi); > + > + xqspi->irq = platform_get_irq(pdev, 0); > + if (xqspi->irq <= 0) { > + ret = -ENXIO; > + dev_err(dev, "irq resource not found\n"); > + goto remove_master; > + } > + ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq, > + 0, pdev->name, master); > + if (ret != 0) { > + ret = -ENXIO; > + dev_err(dev, "request_irq failed\n"); > + goto remove_master; > + } Shouldnt the clk disable be called here. > + if (master->dev.parent == NULL) > + master->dev.parent = &master->dev; > + > + ret = spi_register_master(master); > + if (ret) > + goto clk_dis_all; > + > + return 0; > + > +clk_dis_all: > + clk_disable_unprepare(xqspi->refclk); > +clk_dis_pclk: > + clk_disable_unprepare(xqspi->pclk); > +remove_master: > + spi_master_put(master); > + > + return ret; > +} > + > +/** > + * zynqmp_qspi_remove: Remove method for the QSPI driver > + * @pdev: Pointer to the platform_device structure > + * > + * This function is called if a device is physically removed from the system or > + * if the driver module is being unloaded. It frees all resources allocated to > + * the device. > + * > + * Return: 0 Always > + */ > +static int zynqmp_qspi_remove(struct platform_device *pdev) > +{ > + struct spi_master *master = platform_get_drvdata(pdev); > + struct zynqmp_qspi *xqspi = spi_master_get_devdata(master); > + > + zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0); > + clk_disable_unprepare(xqspi->refclk); > + clk_disable_unprepare(xqspi->pclk); > + > + spi_unregister_master(master); > + > + return 0; > +} > + > +static const struct of_device_id zynqmp_qspi_of_match[] = { > + { .compatible = "xlnx,zynqmp-qspi-1.0", }, > + { /* End of table */ } > +}; > + > +MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match); > + > +static struct platform_driver zynqmp_qspi_driver = { > + .probe = zynqmp_qspi_probe, > + .remove = zynqmp_qspi_remove, > + .driver = { > + .name = "zynqmp-qspi", > + .of_match_table = zynqmp_qspi_of_match, > + .pm = &zynqmp_qspi_dev_pm_ops, > + }, > +}; > + > +module_platform_driver(zynqmp_qspi_driver); > + > +MODULE_AUTHOR("Xilinx, Inc."); > +MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver"); > +MODULE_LICENSE("GPL"); > -- > 2.1.2 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/