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b867eef4cf
The SPIE register contains counts for the TX FIFO so any time the irq
handler was invoked we would attempt to process the RX/TX fifos. Use the
SPIM value to mask the events so that we only process interrupts that
were expected.
This was a latent issue exposed by commit 3282a3da25
("powerpc/64:
Implement soft interrupt replay in C").
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20200904002812.7300-1-chris.packham@alliedtelesis.co.nz
Signed-off-by: Mark Brown <broonie@kernel.org>
854 lines
21 KiB
C
854 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Freescale eSPI controller driver.
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*
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* Copyright 2010 Freescale Semiconductor, Inc.
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*/
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#include <linux/delay.h>
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#include <linux/err.h>
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#include <linux/fsl_devices.h>
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <linux/mm.h>
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#include <linux/of.h>
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#include <linux/of_platform.h>
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#include <linux/platform_device.h>
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#include <linux/spi/spi.h>
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#include <linux/pm_runtime.h>
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#include <sysdev/fsl_soc.h>
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/* eSPI Controller registers */
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#define ESPI_SPMODE 0x00 /* eSPI mode register */
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#define ESPI_SPIE 0x04 /* eSPI event register */
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#define ESPI_SPIM 0x08 /* eSPI mask register */
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#define ESPI_SPCOM 0x0c /* eSPI command register */
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#define ESPI_SPITF 0x10 /* eSPI transmit FIFO access register*/
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#define ESPI_SPIRF 0x14 /* eSPI receive FIFO access register*/
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#define ESPI_SPMODE0 0x20 /* eSPI cs0 mode register */
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#define ESPI_SPMODEx(x) (ESPI_SPMODE0 + (x) * 4)
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/* eSPI Controller mode register definitions */
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#define SPMODE_ENABLE BIT(31)
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#define SPMODE_LOOP BIT(30)
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#define SPMODE_TXTHR(x) ((x) << 8)
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#define SPMODE_RXTHR(x) ((x) << 0)
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/* eSPI Controller CS mode register definitions */
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#define CSMODE_CI_INACTIVEHIGH BIT(31)
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#define CSMODE_CP_BEGIN_EDGECLK BIT(30)
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#define CSMODE_REV BIT(29)
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#define CSMODE_DIV16 BIT(28)
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#define CSMODE_PM(x) ((x) << 24)
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#define CSMODE_POL_1 BIT(20)
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#define CSMODE_LEN(x) ((x) << 16)
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#define CSMODE_BEF(x) ((x) << 12)
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#define CSMODE_AFT(x) ((x) << 8)
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#define CSMODE_CG(x) ((x) << 3)
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#define FSL_ESPI_FIFO_SIZE 32
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#define FSL_ESPI_RXTHR 15
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/* Default mode/csmode for eSPI controller */
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#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(FSL_ESPI_RXTHR))
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#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
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| CSMODE_AFT(0) | CSMODE_CG(1))
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/* SPIE register values */
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#define SPIE_RXCNT(reg) ((reg >> 24) & 0x3F)
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#define SPIE_TXCNT(reg) ((reg >> 16) & 0x3F)
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#define SPIE_TXE BIT(15) /* TX FIFO empty */
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#define SPIE_DON BIT(14) /* TX done */
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#define SPIE_RXT BIT(13) /* RX FIFO threshold */
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#define SPIE_RXF BIT(12) /* RX FIFO full */
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#define SPIE_TXT BIT(11) /* TX FIFO threshold*/
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#define SPIE_RNE BIT(9) /* RX FIFO not empty */
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#define SPIE_TNF BIT(8) /* TX FIFO not full */
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/* SPIM register values */
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#define SPIM_TXE BIT(15) /* TX FIFO empty */
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#define SPIM_DON BIT(14) /* TX done */
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#define SPIM_RXT BIT(13) /* RX FIFO threshold */
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#define SPIM_RXF BIT(12) /* RX FIFO full */
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#define SPIM_TXT BIT(11) /* TX FIFO threshold*/
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#define SPIM_RNE BIT(9) /* RX FIFO not empty */
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#define SPIM_TNF BIT(8) /* TX FIFO not full */
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/* SPCOM register values */
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#define SPCOM_CS(x) ((x) << 30)
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#define SPCOM_DO BIT(28) /* Dual output */
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#define SPCOM_TO BIT(27) /* TX only */
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#define SPCOM_RXSKIP(x) ((x) << 16)
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#define SPCOM_TRANLEN(x) ((x) << 0)
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#define SPCOM_TRANLEN_MAX 0x10000 /* Max transaction length */
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#define AUTOSUSPEND_TIMEOUT 2000
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struct fsl_espi {
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struct device *dev;
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void __iomem *reg_base;
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struct list_head *m_transfers;
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struct spi_transfer *tx_t;
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unsigned int tx_pos;
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bool tx_done;
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struct spi_transfer *rx_t;
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unsigned int rx_pos;
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bool rx_done;
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bool swab;
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unsigned int rxskip;
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spinlock_t lock;
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u32 spibrg; /* SPIBRG input clock */
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struct completion done;
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};
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struct fsl_espi_cs {
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u32 hw_mode;
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};
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static inline u32 fsl_espi_read_reg(struct fsl_espi *espi, int offset)
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{
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return ioread32be(espi->reg_base + offset);
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}
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static inline u16 fsl_espi_read_reg16(struct fsl_espi *espi, int offset)
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{
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return ioread16be(espi->reg_base + offset);
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}
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static inline u8 fsl_espi_read_reg8(struct fsl_espi *espi, int offset)
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{
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return ioread8(espi->reg_base + offset);
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}
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static inline void fsl_espi_write_reg(struct fsl_espi *espi, int offset,
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u32 val)
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{
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iowrite32be(val, espi->reg_base + offset);
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}
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static inline void fsl_espi_write_reg16(struct fsl_espi *espi, int offset,
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u16 val)
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{
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iowrite16be(val, espi->reg_base + offset);
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}
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static inline void fsl_espi_write_reg8(struct fsl_espi *espi, int offset,
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u8 val)
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{
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iowrite8(val, espi->reg_base + offset);
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}
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static int fsl_espi_check_message(struct spi_message *m)
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{
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struct fsl_espi *espi = spi_master_get_devdata(m->spi->master);
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struct spi_transfer *t, *first;
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if (m->frame_length > SPCOM_TRANLEN_MAX) {
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dev_err(espi->dev, "message too long, size is %u bytes\n",
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m->frame_length);
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return -EMSGSIZE;
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}
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first = list_first_entry(&m->transfers, struct spi_transfer,
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transfer_list);
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list_for_each_entry(t, &m->transfers, transfer_list) {
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if (first->bits_per_word != t->bits_per_word ||
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first->speed_hz != t->speed_hz) {
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dev_err(espi->dev, "bits_per_word/speed_hz should be the same for all transfers\n");
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return -EINVAL;
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}
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}
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/* ESPI supports MSB-first transfers for word size 8 / 16 only */
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if (!(m->spi->mode & SPI_LSB_FIRST) && first->bits_per_word != 8 &&
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first->bits_per_word != 16) {
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dev_err(espi->dev,
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"MSB-first transfer not supported for wordsize %u\n",
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first->bits_per_word);
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return -EINVAL;
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}
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return 0;
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}
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static unsigned int fsl_espi_check_rxskip_mode(struct spi_message *m)
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{
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struct spi_transfer *t;
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unsigned int i = 0, rxskip = 0;
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/*
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* prerequisites for ESPI rxskip mode:
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* - message has two transfers
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* - first transfer is a write and second is a read
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*
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* In addition the current low-level transfer mechanism requires
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* that the rxskip bytes fit into the TX FIFO. Else the transfer
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* would hang because after the first FSL_ESPI_FIFO_SIZE bytes
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* the TX FIFO isn't re-filled.
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*/
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list_for_each_entry(t, &m->transfers, transfer_list) {
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if (i == 0) {
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if (!t->tx_buf || t->rx_buf ||
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t->len > FSL_ESPI_FIFO_SIZE)
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return 0;
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rxskip = t->len;
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} else if (i == 1) {
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if (t->tx_buf || !t->rx_buf)
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return 0;
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}
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i++;
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}
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return i == 2 ? rxskip : 0;
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}
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static void fsl_espi_fill_tx_fifo(struct fsl_espi *espi, u32 events)
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{
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u32 tx_fifo_avail;
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unsigned int tx_left;
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const void *tx_buf;
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/* if events is zero transfer has not started and tx fifo is empty */
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tx_fifo_avail = events ? SPIE_TXCNT(events) : FSL_ESPI_FIFO_SIZE;
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start:
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tx_left = espi->tx_t->len - espi->tx_pos;
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tx_buf = espi->tx_t->tx_buf;
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while (tx_fifo_avail >= min(4U, tx_left) && tx_left) {
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if (tx_left >= 4) {
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if (!tx_buf)
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fsl_espi_write_reg(espi, ESPI_SPITF, 0);
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else if (espi->swab)
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fsl_espi_write_reg(espi, ESPI_SPITF,
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swahb32p(tx_buf + espi->tx_pos));
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else
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fsl_espi_write_reg(espi, ESPI_SPITF,
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*(u32 *)(tx_buf + espi->tx_pos));
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espi->tx_pos += 4;
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tx_left -= 4;
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tx_fifo_avail -= 4;
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} else if (tx_left >= 2 && tx_buf && espi->swab) {
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fsl_espi_write_reg16(espi, ESPI_SPITF,
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swab16p(tx_buf + espi->tx_pos));
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espi->tx_pos += 2;
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tx_left -= 2;
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tx_fifo_avail -= 2;
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} else {
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if (!tx_buf)
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fsl_espi_write_reg8(espi, ESPI_SPITF, 0);
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else
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fsl_espi_write_reg8(espi, ESPI_SPITF,
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*(u8 *)(tx_buf + espi->tx_pos));
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espi->tx_pos += 1;
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tx_left -= 1;
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tx_fifo_avail -= 1;
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}
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}
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if (!tx_left) {
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/* Last transfer finished, in rxskip mode only one is needed */
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if (list_is_last(&espi->tx_t->transfer_list,
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espi->m_transfers) || espi->rxskip) {
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espi->tx_done = true;
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return;
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}
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espi->tx_t = list_next_entry(espi->tx_t, transfer_list);
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espi->tx_pos = 0;
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/* continue with next transfer if tx fifo is not full */
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if (tx_fifo_avail)
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goto start;
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}
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}
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static void fsl_espi_read_rx_fifo(struct fsl_espi *espi, u32 events)
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{
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u32 rx_fifo_avail = SPIE_RXCNT(events);
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unsigned int rx_left;
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void *rx_buf;
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start:
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rx_left = espi->rx_t->len - espi->rx_pos;
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rx_buf = espi->rx_t->rx_buf;
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while (rx_fifo_avail >= min(4U, rx_left) && rx_left) {
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if (rx_left >= 4) {
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u32 val = fsl_espi_read_reg(espi, ESPI_SPIRF);
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if (rx_buf && espi->swab)
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*(u32 *)(rx_buf + espi->rx_pos) = swahb32(val);
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else if (rx_buf)
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*(u32 *)(rx_buf + espi->rx_pos) = val;
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espi->rx_pos += 4;
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rx_left -= 4;
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rx_fifo_avail -= 4;
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} else if (rx_left >= 2 && rx_buf && espi->swab) {
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u16 val = fsl_espi_read_reg16(espi, ESPI_SPIRF);
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*(u16 *)(rx_buf + espi->rx_pos) = swab16(val);
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espi->rx_pos += 2;
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rx_left -= 2;
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rx_fifo_avail -= 2;
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} else {
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u8 val = fsl_espi_read_reg8(espi, ESPI_SPIRF);
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if (rx_buf)
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*(u8 *)(rx_buf + espi->rx_pos) = val;
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espi->rx_pos += 1;
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rx_left -= 1;
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rx_fifo_avail -= 1;
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}
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}
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if (!rx_left) {
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if (list_is_last(&espi->rx_t->transfer_list,
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espi->m_transfers)) {
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espi->rx_done = true;
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return;
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}
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espi->rx_t = list_next_entry(espi->rx_t, transfer_list);
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espi->rx_pos = 0;
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/* continue with next transfer if rx fifo is not empty */
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if (rx_fifo_avail)
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goto start;
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}
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}
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static void fsl_espi_setup_transfer(struct spi_device *spi,
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struct spi_transfer *t)
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{
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struct fsl_espi *espi = spi_master_get_devdata(spi->master);
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int bits_per_word = t ? t->bits_per_word : spi->bits_per_word;
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u32 pm, hz = t ? t->speed_hz : spi->max_speed_hz;
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struct fsl_espi_cs *cs = spi_get_ctldata(spi);
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u32 hw_mode_old = cs->hw_mode;
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/* mask out bits we are going to set */
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cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
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cs->hw_mode |= CSMODE_LEN(bits_per_word - 1);
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pm = DIV_ROUND_UP(espi->spibrg, hz * 4) - 1;
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if (pm > 15) {
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cs->hw_mode |= CSMODE_DIV16;
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pm = DIV_ROUND_UP(espi->spibrg, hz * 16 * 4) - 1;
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}
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cs->hw_mode |= CSMODE_PM(pm);
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/* don't write the mode register if the mode doesn't change */
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if (cs->hw_mode != hw_mode_old)
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fsl_espi_write_reg(espi, ESPI_SPMODEx(spi->chip_select),
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cs->hw_mode);
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}
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static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
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{
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struct fsl_espi *espi = spi_master_get_devdata(spi->master);
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unsigned int rx_len = t->len;
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u32 mask, spcom;
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int ret;
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reinit_completion(&espi->done);
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/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
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spcom = SPCOM_CS(spi->chip_select);
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spcom |= SPCOM_TRANLEN(t->len - 1);
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/* configure RXSKIP mode */
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if (espi->rxskip) {
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spcom |= SPCOM_RXSKIP(espi->rxskip);
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rx_len = t->len - espi->rxskip;
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if (t->rx_nbits == SPI_NBITS_DUAL)
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spcom |= SPCOM_DO;
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}
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fsl_espi_write_reg(espi, ESPI_SPCOM, spcom);
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/* enable interrupts */
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mask = SPIM_DON;
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if (rx_len > FSL_ESPI_FIFO_SIZE)
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mask |= SPIM_RXT;
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fsl_espi_write_reg(espi, ESPI_SPIM, mask);
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/* Prevent filling the fifo from getting interrupted */
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spin_lock_irq(&espi->lock);
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fsl_espi_fill_tx_fifo(espi, 0);
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spin_unlock_irq(&espi->lock);
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/* Won't hang up forever, SPI bus sometimes got lost interrupts... */
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ret = wait_for_completion_timeout(&espi->done, 2 * HZ);
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if (ret == 0)
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dev_err(espi->dev, "Transfer timed out!\n");
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/* disable rx ints */
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fsl_espi_write_reg(espi, ESPI_SPIM, 0);
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return ret == 0 ? -ETIMEDOUT : 0;
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}
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static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans)
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{
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struct fsl_espi *espi = spi_master_get_devdata(m->spi->master);
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struct spi_device *spi = m->spi;
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int ret;
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/* In case of LSB-first and bits_per_word > 8 byte-swap all words */
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espi->swab = spi->mode & SPI_LSB_FIRST && trans->bits_per_word > 8;
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espi->m_transfers = &m->transfers;
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espi->tx_t = list_first_entry(&m->transfers, struct spi_transfer,
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transfer_list);
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espi->tx_pos = 0;
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espi->tx_done = false;
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espi->rx_t = list_first_entry(&m->transfers, struct spi_transfer,
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transfer_list);
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espi->rx_pos = 0;
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espi->rx_done = false;
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espi->rxskip = fsl_espi_check_rxskip_mode(m);
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if (trans->rx_nbits == SPI_NBITS_DUAL && !espi->rxskip) {
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dev_err(espi->dev, "Dual output mode requires RXSKIP mode!\n");
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return -EINVAL;
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}
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/* In RXSKIP mode skip first transfer for reads */
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if (espi->rxskip)
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espi->rx_t = list_next_entry(espi->rx_t, transfer_list);
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fsl_espi_setup_transfer(spi, trans);
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ret = fsl_espi_bufs(spi, trans);
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spi_transfer_delay_exec(trans);
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return ret;
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}
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static int fsl_espi_do_one_msg(struct spi_master *master,
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struct spi_message *m)
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{
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unsigned int delay_usecs = 0, rx_nbits = 0;
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unsigned int delay_nsecs = 0, delay_nsecs1 = 0;
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struct spi_transfer *t, trans = {};
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int ret;
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ret = fsl_espi_check_message(m);
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if (ret)
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goto out;
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list_for_each_entry(t, &m->transfers, transfer_list) {
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if (t->delay_usecs) {
|
|
if (t->delay_usecs > delay_usecs) {
|
|
delay_usecs = t->delay_usecs;
|
|
delay_nsecs = delay_usecs * 1000;
|
|
}
|
|
} else {
|
|
delay_nsecs1 = spi_delay_to_ns(&t->delay, t);
|
|
if (delay_nsecs1 > delay_nsecs)
|
|
delay_nsecs = delay_nsecs1;
|
|
}
|
|
if (t->rx_nbits > rx_nbits)
|
|
rx_nbits = t->rx_nbits;
|
|
}
|
|
|
|
t = list_first_entry(&m->transfers, struct spi_transfer,
|
|
transfer_list);
|
|
|
|
trans.len = m->frame_length;
|
|
trans.speed_hz = t->speed_hz;
|
|
trans.bits_per_word = t->bits_per_word;
|
|
trans.delay.value = delay_nsecs;
|
|
trans.delay.unit = SPI_DELAY_UNIT_NSECS;
|
|
trans.rx_nbits = rx_nbits;
|
|
|
|
if (trans.len)
|
|
ret = fsl_espi_trans(m, &trans);
|
|
|
|
m->actual_length = ret ? 0 : trans.len;
|
|
out:
|
|
if (m->status == -EINPROGRESS)
|
|
m->status = ret;
|
|
|
|
spi_finalize_current_message(master);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int fsl_espi_setup(struct spi_device *spi)
|
|
{
|
|
struct fsl_espi *espi;
|
|
u32 loop_mode;
|
|
struct fsl_espi_cs *cs = spi_get_ctldata(spi);
|
|
|
|
if (!cs) {
|
|
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
|
|
if (!cs)
|
|
return -ENOMEM;
|
|
spi_set_ctldata(spi, cs);
|
|
}
|
|
|
|
espi = spi_master_get_devdata(spi->master);
|
|
|
|
pm_runtime_get_sync(espi->dev);
|
|
|
|
cs->hw_mode = fsl_espi_read_reg(espi, ESPI_SPMODEx(spi->chip_select));
|
|
/* mask out bits we are going to set */
|
|
cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
|
|
| CSMODE_REV);
|
|
|
|
if (spi->mode & SPI_CPHA)
|
|
cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
|
|
if (spi->mode & SPI_CPOL)
|
|
cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
|
|
if (!(spi->mode & SPI_LSB_FIRST))
|
|
cs->hw_mode |= CSMODE_REV;
|
|
|
|
/* Handle the loop mode */
|
|
loop_mode = fsl_espi_read_reg(espi, ESPI_SPMODE);
|
|
loop_mode &= ~SPMODE_LOOP;
|
|
if (spi->mode & SPI_LOOP)
|
|
loop_mode |= SPMODE_LOOP;
|
|
fsl_espi_write_reg(espi, ESPI_SPMODE, loop_mode);
|
|
|
|
fsl_espi_setup_transfer(spi, NULL);
|
|
|
|
pm_runtime_mark_last_busy(espi->dev);
|
|
pm_runtime_put_autosuspend(espi->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void fsl_espi_cleanup(struct spi_device *spi)
|
|
{
|
|
struct fsl_espi_cs *cs = spi_get_ctldata(spi);
|
|
|
|
kfree(cs);
|
|
spi_set_ctldata(spi, NULL);
|
|
}
|
|
|
|
static void fsl_espi_cpu_irq(struct fsl_espi *espi, u32 events)
|
|
{
|
|
if (!espi->rx_done)
|
|
fsl_espi_read_rx_fifo(espi, events);
|
|
|
|
if (!espi->tx_done)
|
|
fsl_espi_fill_tx_fifo(espi, events);
|
|
|
|
if (!espi->tx_done || !espi->rx_done)
|
|
return;
|
|
|
|
/* we're done, but check for errors before returning */
|
|
events = fsl_espi_read_reg(espi, ESPI_SPIE);
|
|
|
|
if (!(events & SPIE_DON))
|
|
dev_err(espi->dev,
|
|
"Transfer done but SPIE_DON isn't set!\n");
|
|
|
|
if (SPIE_RXCNT(events) || SPIE_TXCNT(events) != FSL_ESPI_FIFO_SIZE) {
|
|
dev_err(espi->dev, "Transfer done but rx/tx fifo's aren't empty!\n");
|
|
dev_err(espi->dev, "SPIE_RXCNT = %d, SPIE_TXCNT = %d\n",
|
|
SPIE_RXCNT(events), SPIE_TXCNT(events));
|
|
}
|
|
|
|
complete(&espi->done);
|
|
}
|
|
|
|
static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
|
|
{
|
|
struct fsl_espi *espi = context_data;
|
|
u32 events, mask;
|
|
|
|
spin_lock(&espi->lock);
|
|
|
|
/* Get interrupt events(tx/rx) */
|
|
events = fsl_espi_read_reg(espi, ESPI_SPIE);
|
|
mask = fsl_espi_read_reg(espi, ESPI_SPIM);
|
|
if (!(events & mask)) {
|
|
spin_unlock(&espi->lock);
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
dev_vdbg(espi->dev, "%s: events %x\n", __func__, events);
|
|
|
|
fsl_espi_cpu_irq(espi, events);
|
|
|
|
/* Clear the events */
|
|
fsl_espi_write_reg(espi, ESPI_SPIE, events);
|
|
|
|
spin_unlock(&espi->lock);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int fsl_espi_runtime_suspend(struct device *dev)
|
|
{
|
|
struct spi_master *master = dev_get_drvdata(dev);
|
|
struct fsl_espi *espi = spi_master_get_devdata(master);
|
|
u32 regval;
|
|
|
|
regval = fsl_espi_read_reg(espi, ESPI_SPMODE);
|
|
regval &= ~SPMODE_ENABLE;
|
|
fsl_espi_write_reg(espi, ESPI_SPMODE, regval);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int fsl_espi_runtime_resume(struct device *dev)
|
|
{
|
|
struct spi_master *master = dev_get_drvdata(dev);
|
|
struct fsl_espi *espi = spi_master_get_devdata(master);
|
|
u32 regval;
|
|
|
|
regval = fsl_espi_read_reg(espi, ESPI_SPMODE);
|
|
regval |= SPMODE_ENABLE;
|
|
fsl_espi_write_reg(espi, ESPI_SPMODE, regval);
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static size_t fsl_espi_max_message_size(struct spi_device *spi)
|
|
{
|
|
return SPCOM_TRANLEN_MAX;
|
|
}
|
|
|
|
static void fsl_espi_init_regs(struct device *dev, bool initial)
|
|
{
|
|
struct spi_master *master = dev_get_drvdata(dev);
|
|
struct fsl_espi *espi = spi_master_get_devdata(master);
|
|
struct device_node *nc;
|
|
u32 csmode, cs, prop;
|
|
int ret;
|
|
|
|
/* SPI controller initializations */
|
|
fsl_espi_write_reg(espi, ESPI_SPMODE, 0);
|
|
fsl_espi_write_reg(espi, ESPI_SPIM, 0);
|
|
fsl_espi_write_reg(espi, ESPI_SPCOM, 0);
|
|
fsl_espi_write_reg(espi, ESPI_SPIE, 0xffffffff);
|
|
|
|
/* Init eSPI CS mode register */
|
|
for_each_available_child_of_node(master->dev.of_node, nc) {
|
|
/* get chip select */
|
|
ret = of_property_read_u32(nc, "reg", &cs);
|
|
if (ret || cs >= master->num_chipselect)
|
|
continue;
|
|
|
|
csmode = CSMODE_INIT_VAL;
|
|
|
|
/* check if CSBEF is set in device tree */
|
|
ret = of_property_read_u32(nc, "fsl,csbef", &prop);
|
|
if (!ret) {
|
|
csmode &= ~(CSMODE_BEF(0xf));
|
|
csmode |= CSMODE_BEF(prop);
|
|
}
|
|
|
|
/* check if CSAFT is set in device tree */
|
|
ret = of_property_read_u32(nc, "fsl,csaft", &prop);
|
|
if (!ret) {
|
|
csmode &= ~(CSMODE_AFT(0xf));
|
|
csmode |= CSMODE_AFT(prop);
|
|
}
|
|
|
|
fsl_espi_write_reg(espi, ESPI_SPMODEx(cs), csmode);
|
|
|
|
if (initial)
|
|
dev_info(dev, "cs=%u, init_csmode=0x%x\n", cs, csmode);
|
|
}
|
|
|
|
/* Enable SPI interface */
|
|
fsl_espi_write_reg(espi, ESPI_SPMODE, SPMODE_INIT_VAL | SPMODE_ENABLE);
|
|
}
|
|
|
|
static int fsl_espi_probe(struct device *dev, struct resource *mem,
|
|
unsigned int irq, unsigned int num_cs)
|
|
{
|
|
struct spi_master *master;
|
|
struct fsl_espi *espi;
|
|
int ret;
|
|
|
|
master = spi_alloc_master(dev, sizeof(struct fsl_espi));
|
|
if (!master)
|
|
return -ENOMEM;
|
|
|
|
dev_set_drvdata(dev, master);
|
|
|
|
master->mode_bits = SPI_RX_DUAL | SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
|
|
SPI_LSB_FIRST | SPI_LOOP;
|
|
master->dev.of_node = dev->of_node;
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
|
|
master->setup = fsl_espi_setup;
|
|
master->cleanup = fsl_espi_cleanup;
|
|
master->transfer_one_message = fsl_espi_do_one_msg;
|
|
master->auto_runtime_pm = true;
|
|
master->max_message_size = fsl_espi_max_message_size;
|
|
master->num_chipselect = num_cs;
|
|
|
|
espi = spi_master_get_devdata(master);
|
|
spin_lock_init(&espi->lock);
|
|
|
|
espi->dev = dev;
|
|
espi->spibrg = fsl_get_sys_freq();
|
|
if (espi->spibrg == -1) {
|
|
dev_err(dev, "Can't get sys frequency!\n");
|
|
ret = -EINVAL;
|
|
goto err_probe;
|
|
}
|
|
/* determined by clock divider fields DIV16/PM in register SPMODEx */
|
|
master->min_speed_hz = DIV_ROUND_UP(espi->spibrg, 4 * 16 * 16);
|
|
master->max_speed_hz = DIV_ROUND_UP(espi->spibrg, 4);
|
|
|
|
init_completion(&espi->done);
|
|
|
|
espi->reg_base = devm_ioremap_resource(dev, mem);
|
|
if (IS_ERR(espi->reg_base)) {
|
|
ret = PTR_ERR(espi->reg_base);
|
|
goto err_probe;
|
|
}
|
|
|
|
/* Register for SPI Interrupt */
|
|
ret = devm_request_irq(dev, irq, fsl_espi_irq, 0, "fsl_espi", espi);
|
|
if (ret)
|
|
goto err_probe;
|
|
|
|
fsl_espi_init_regs(dev, true);
|
|
|
|
pm_runtime_set_autosuspend_delay(dev, AUTOSUSPEND_TIMEOUT);
|
|
pm_runtime_use_autosuspend(dev);
|
|
pm_runtime_set_active(dev);
|
|
pm_runtime_enable(dev);
|
|
pm_runtime_get_sync(dev);
|
|
|
|
ret = devm_spi_register_master(dev, master);
|
|
if (ret < 0)
|
|
goto err_pm;
|
|
|
|
dev_info(dev, "at 0x%p (irq = %u)\n", espi->reg_base, irq);
|
|
|
|
pm_runtime_mark_last_busy(dev);
|
|
pm_runtime_put_autosuspend(dev);
|
|
|
|
return 0;
|
|
|
|
err_pm:
|
|
pm_runtime_put_noidle(dev);
|
|
pm_runtime_disable(dev);
|
|
pm_runtime_set_suspended(dev);
|
|
err_probe:
|
|
spi_master_put(master);
|
|
return ret;
|
|
}
|
|
|
|
static int of_fsl_espi_get_chipselects(struct device *dev)
|
|
{
|
|
struct device_node *np = dev->of_node;
|
|
u32 num_cs;
|
|
int ret;
|
|
|
|
ret = of_property_read_u32(np, "fsl,espi-num-chipselects", &num_cs);
|
|
if (ret) {
|
|
dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
|
|
return 0;
|
|
}
|
|
|
|
return num_cs;
|
|
}
|
|
|
|
static int of_fsl_espi_probe(struct platform_device *ofdev)
|
|
{
|
|
struct device *dev = &ofdev->dev;
|
|
struct device_node *np = ofdev->dev.of_node;
|
|
struct resource mem;
|
|
unsigned int irq, num_cs;
|
|
int ret;
|
|
|
|
if (of_property_read_bool(np, "mode")) {
|
|
dev_err(dev, "mode property is not supported on ESPI!\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
num_cs = of_fsl_espi_get_chipselects(dev);
|
|
if (!num_cs)
|
|
return -EINVAL;
|
|
|
|
ret = of_address_to_resource(np, 0, &mem);
|
|
if (ret)
|
|
return ret;
|
|
|
|
irq = irq_of_parse_and_map(np, 0);
|
|
if (!irq)
|
|
return -EINVAL;
|
|
|
|
return fsl_espi_probe(dev, &mem, irq, num_cs);
|
|
}
|
|
|
|
static int of_fsl_espi_remove(struct platform_device *dev)
|
|
{
|
|
pm_runtime_disable(&dev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int of_fsl_espi_suspend(struct device *dev)
|
|
{
|
|
struct spi_master *master = dev_get_drvdata(dev);
|
|
int ret;
|
|
|
|
ret = spi_master_suspend(master);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return pm_runtime_force_suspend(dev);
|
|
}
|
|
|
|
static int of_fsl_espi_resume(struct device *dev)
|
|
{
|
|
struct spi_master *master = dev_get_drvdata(dev);
|
|
int ret;
|
|
|
|
fsl_espi_init_regs(dev, false);
|
|
|
|
ret = pm_runtime_force_resume(dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
return spi_master_resume(master);
|
|
}
|
|
#endif /* CONFIG_PM_SLEEP */
|
|
|
|
static const struct dev_pm_ops espi_pm = {
|
|
SET_RUNTIME_PM_OPS(fsl_espi_runtime_suspend,
|
|
fsl_espi_runtime_resume, NULL)
|
|
SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume)
|
|
};
|
|
|
|
static const struct of_device_id of_fsl_espi_match[] = {
|
|
{ .compatible = "fsl,mpc8536-espi" },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
|
|
|
|
static struct platform_driver fsl_espi_driver = {
|
|
.driver = {
|
|
.name = "fsl_espi",
|
|
.of_match_table = of_fsl_espi_match,
|
|
.pm = &espi_pm,
|
|
},
|
|
.probe = of_fsl_espi_probe,
|
|
.remove = of_fsl_espi_remove,
|
|
};
|
|
module_platform_driver(fsl_espi_driver);
|
|
|
|
MODULE_AUTHOR("Mingkai Hu");
|
|
MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
|
|
MODULE_LICENSE("GPL");
|