diff options
Diffstat (limited to 'drivers/spi/spi-dw-mid.c')
-rw-r--r-- | drivers/spi/spi-dw-mid.c | 322 |
1 files changed, 0 insertions, 322 deletions
diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c deleted file mode 100644 index 0d86c37e0aeb..000000000000 --- a/drivers/spi/spi-dw-mid.c +++ /dev/null @@ -1,322 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Special handling for DW core on Intel MID platform - * - * Copyright (c) 2009, 2014 Intel Corporation. - */ - -#include <linux/dma-mapping.h> -#include <linux/dmaengine.h> -#include <linux/interrupt.h> -#include <linux/slab.h> -#include <linux/spi/spi.h> -#include <linux/types.h> - -#include "spi-dw.h" - -#ifdef CONFIG_SPI_DW_MID_DMA -#include <linux/pci.h> -#include <linux/platform_data/dma-dw.h> - -#define RX_BUSY 0 -#define TX_BUSY 1 - -static struct dw_dma_slave mid_dma_tx = { .dst_id = 1 }; -static struct dw_dma_slave mid_dma_rx = { .src_id = 0 }; - -static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param) -{ - struct dw_dma_slave *s = param; - - if (s->dma_dev != chan->device->dev) - return false; - - chan->private = s; - return true; -} - -static int mid_spi_dma_init(struct dw_spi *dws) -{ - struct pci_dev *dma_dev; - struct dw_dma_slave *tx = dws->dma_tx; - struct dw_dma_slave *rx = dws->dma_rx; - dma_cap_mask_t mask; - - /* - * Get pci device for DMA controller, currently it could only - * be the DMA controller of Medfield - */ - dma_dev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL); - if (!dma_dev) - return -ENODEV; - - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - - /* 1. Init rx channel */ - rx->dma_dev = &dma_dev->dev; - dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, rx); - if (!dws->rxchan) - goto err_exit; - dws->master->dma_rx = dws->rxchan; - - /* 2. Init tx channel */ - tx->dma_dev = &dma_dev->dev; - dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, tx); - if (!dws->txchan) - goto free_rxchan; - dws->master->dma_tx = dws->txchan; - - dws->dma_inited = 1; - return 0; - -free_rxchan: - dma_release_channel(dws->rxchan); -err_exit: - return -EBUSY; -} - -static void mid_spi_dma_exit(struct dw_spi *dws) -{ - if (!dws->dma_inited) - return; - - dmaengine_terminate_sync(dws->txchan); - dma_release_channel(dws->txchan); - - dmaengine_terminate_sync(dws->rxchan); - dma_release_channel(dws->rxchan); -} - -static irqreturn_t dma_transfer(struct dw_spi *dws) -{ - u16 irq_status = dw_readl(dws, DW_SPI_ISR); - - if (!irq_status) - return IRQ_NONE; - - dw_readl(dws, DW_SPI_ICR); - spi_reset_chip(dws); - - dev_err(&dws->master->dev, "%s: FIFO overrun/underrun\n", __func__); - dws->master->cur_msg->status = -EIO; - spi_finalize_current_transfer(dws->master); - return IRQ_HANDLED; -} - -static bool mid_spi_can_dma(struct spi_controller *master, - struct spi_device *spi, struct spi_transfer *xfer) -{ - struct dw_spi *dws = spi_controller_get_devdata(master); - - if (!dws->dma_inited) - return false; - - return xfer->len > dws->fifo_len; -} - -static enum dma_slave_buswidth convert_dma_width(u32 dma_width) { - if (dma_width == 1) - return DMA_SLAVE_BUSWIDTH_1_BYTE; - else if (dma_width == 2) - return DMA_SLAVE_BUSWIDTH_2_BYTES; - - return DMA_SLAVE_BUSWIDTH_UNDEFINED; -} - -/* - * dws->dma_chan_busy is set before the dma transfer starts, callback for tx - * channel will clear a corresponding bit. - */ -static void dw_spi_dma_tx_done(void *arg) -{ - struct dw_spi *dws = arg; - - clear_bit(TX_BUSY, &dws->dma_chan_busy); - if (test_bit(RX_BUSY, &dws->dma_chan_busy)) - return; - spi_finalize_current_transfer(dws->master); -} - -static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws, - struct spi_transfer *xfer) -{ - struct dma_slave_config txconf; - struct dma_async_tx_descriptor *txdesc; - - if (!xfer->tx_buf) - return NULL; - - txconf.direction = DMA_MEM_TO_DEV; - txconf.dst_addr = dws->dma_addr; - txconf.dst_maxburst = 16; - txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - txconf.dst_addr_width = convert_dma_width(dws->dma_width); - txconf.device_fc = false; - - dmaengine_slave_config(dws->txchan, &txconf); - - txdesc = dmaengine_prep_slave_sg(dws->txchan, - xfer->tx_sg.sgl, - xfer->tx_sg.nents, - DMA_MEM_TO_DEV, - DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!txdesc) - return NULL; - - txdesc->callback = dw_spi_dma_tx_done; - txdesc->callback_param = dws; - - return txdesc; -} - -/* - * dws->dma_chan_busy is set before the dma transfer starts, callback for rx - * channel will clear a corresponding bit. - */ -static void dw_spi_dma_rx_done(void *arg) -{ - struct dw_spi *dws = arg; - - clear_bit(RX_BUSY, &dws->dma_chan_busy); - if (test_bit(TX_BUSY, &dws->dma_chan_busy)) - return; - spi_finalize_current_transfer(dws->master); -} - -static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, - struct spi_transfer *xfer) -{ - struct dma_slave_config rxconf; - struct dma_async_tx_descriptor *rxdesc; - - if (!xfer->rx_buf) - return NULL; - - rxconf.direction = DMA_DEV_TO_MEM; - rxconf.src_addr = dws->dma_addr; - rxconf.src_maxburst = 16; - rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - rxconf.src_addr_width = convert_dma_width(dws->dma_width); - rxconf.device_fc = false; - - dmaengine_slave_config(dws->rxchan, &rxconf); - - rxdesc = dmaengine_prep_slave_sg(dws->rxchan, - xfer->rx_sg.sgl, - xfer->rx_sg.nents, - DMA_DEV_TO_MEM, - DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!rxdesc) - return NULL; - - rxdesc->callback = dw_spi_dma_rx_done; - rxdesc->callback_param = dws; - - return rxdesc; -} - -static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer) -{ - u16 dma_ctrl = 0; - - dw_writel(dws, DW_SPI_DMARDLR, 0xf); - dw_writel(dws, DW_SPI_DMATDLR, 0x10); - - if (xfer->tx_buf) - dma_ctrl |= SPI_DMA_TDMAE; - if (xfer->rx_buf) - dma_ctrl |= SPI_DMA_RDMAE; - dw_writel(dws, DW_SPI_DMACR, dma_ctrl); - - /* Set the interrupt mask */ - spi_umask_intr(dws, SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI); - - dws->transfer_handler = dma_transfer; - - return 0; -} - -static int mid_spi_dma_transfer(struct dw_spi *dws, struct spi_transfer *xfer) -{ - struct dma_async_tx_descriptor *txdesc, *rxdesc; - - /* Prepare the TX dma transfer */ - txdesc = dw_spi_dma_prepare_tx(dws, xfer); - - /* Prepare the RX dma transfer */ - rxdesc = dw_spi_dma_prepare_rx(dws, xfer); - - /* rx must be started before tx due to spi instinct */ - if (rxdesc) { - set_bit(RX_BUSY, &dws->dma_chan_busy); - dmaengine_submit(rxdesc); - dma_async_issue_pending(dws->rxchan); - } - - if (txdesc) { - set_bit(TX_BUSY, &dws->dma_chan_busy); - dmaengine_submit(txdesc); - dma_async_issue_pending(dws->txchan); - } - - return 0; -} - -static void mid_spi_dma_stop(struct dw_spi *dws) -{ - if (test_bit(TX_BUSY, &dws->dma_chan_busy)) { - dmaengine_terminate_sync(dws->txchan); - clear_bit(TX_BUSY, &dws->dma_chan_busy); - } - if (test_bit(RX_BUSY, &dws->dma_chan_busy)) { - dmaengine_terminate_sync(dws->rxchan); - clear_bit(RX_BUSY, &dws->dma_chan_busy); - } -} - -static const struct dw_spi_dma_ops mid_dma_ops = { - .dma_init = mid_spi_dma_init, - .dma_exit = mid_spi_dma_exit, - .dma_setup = mid_spi_dma_setup, - .can_dma = mid_spi_can_dma, - .dma_transfer = mid_spi_dma_transfer, - .dma_stop = mid_spi_dma_stop, -}; -#endif - -/* Some specific info for SPI0 controller on Intel MID */ - -/* HW info for MRST Clk Control Unit, 32b reg per controller */ -#define MRST_SPI_CLK_BASE 100000000 /* 100m */ -#define MRST_CLK_SPI_REG 0xff11d86c -#define CLK_SPI_BDIV_OFFSET 0 -#define CLK_SPI_BDIV_MASK 0x00000007 -#define CLK_SPI_CDIV_OFFSET 9 -#define CLK_SPI_CDIV_MASK 0x00000e00 -#define CLK_SPI_DISABLE_OFFSET 8 - -int dw_spi_mid_init(struct dw_spi *dws) -{ - void __iomem *clk_reg; - u32 clk_cdiv; - - clk_reg = ioremap(MRST_CLK_SPI_REG, 16); - if (!clk_reg) - return -ENOMEM; - - /* Get SPI controller operating freq info */ - clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32)); - clk_cdiv &= CLK_SPI_CDIV_MASK; - clk_cdiv >>= CLK_SPI_CDIV_OFFSET; - dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1); - - iounmap(clk_reg); - -#ifdef CONFIG_SPI_DW_MID_DMA - dws->dma_tx = &mid_dma_tx; - dws->dma_rx = &mid_dma_rx; - dws->dma_ops = &mid_dma_ops; -#endif - return 0; -} |