Plugin set cs API to the SPI framework so that framework can do chipselect assert de-assert during SPI transfers.
Signed-off-by: Dilip Kota <[email protected]> --- drivers/spi/spi-geni-qcom.c | 65 ++++++++++++++++++++++++++++++++------------- 1 file changed, 46 insertions(+), 19 deletions(-) diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c index 949b853..5cfb4f2 100644 --- a/drivers/spi/spi-geni-qcom.c +++ b/drivers/spi/spi-geni-qcom.c @@ -66,6 +66,13 @@ static irqreturn_t geni_spi_isr(int irq, void *data); +/* SPI M_COMMAND OPCODE */ +enum spi_mcmd_code { + CMD_NONE, + CMD_XFER, + CMD_CS, +}; + struct spi_geni_master { struct geni_se se; struct device *dev; @@ -81,8 +88,12 @@ struct spi_geni_master { struct completion xfer_done; unsigned int oversampling; spinlock_t lock; + unsigned int cur_mcmd; }; +static void handle_fifo_timeout(struct spi_master *spi, + struct spi_message *msg); + static int get_spi_clk_cfg(unsigned int speed_hz, struct spi_geni_master *mas, unsigned int *clk_idx, @@ -113,6 +124,31 @@ static int get_spi_clk_cfg(unsigned int speed_hz, return ret; } +static void spi_geni_set_cs(struct spi_device *slv, bool set_flag) +{ + struct spi_geni_master *mas = spi_master_get_devdata(slv->master); + struct spi_master *spi = dev_get_drvdata(mas->dev); + struct geni_se *se = &mas->se; + unsigned long timeout; + + reinit_completion(&mas->xfer_done); + pm_runtime_get_sync(mas->dev); + if (!(slv->mode & SPI_CS_HIGH)) + set_flag = !set_flag; + + mas->cur_mcmd = CMD_CS; + if (set_flag) + geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0); + else + geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0); + + timeout = wait_for_completion_timeout(&mas->xfer_done, HZ); + if (!timeout) + handle_fifo_timeout(spi, NULL); + + pm_runtime_put(mas->dev); +} + static void spi_setup_word_len(struct spi_geni_master *mas, u16 mode, unsigned int bits_per_word) { @@ -249,7 +285,7 @@ static void setup_fifo_xfer(struct spi_transfer *xfer, struct spi_geni_master *mas, u16 mode, struct spi_master *spi) { - u32 m_cmd = 0, m_param = 0; + u32 m_cmd = 0; u32 spi_tx_cfg, trans_len; struct geni_se *se = &mas->se; @@ -305,21 +341,7 @@ static void setup_fifo_xfer(struct spi_transfer *xfer, trans_len = (xfer->len / bytes_per_word) & TRANS_LEN_MSK; } - /* - * If CS change flag is set, then toggle the CS line in between - * transfers and keep CS asserted after the last transfer. - * Else if keep CS flag asserted in between transfers and de-assert - * CS after the last message. - */ - if (xfer->cs_change) { - if (list_is_last(&xfer->transfer_list, - &spi->cur_msg->transfers)) - m_param = FRAGMENTATION; - } else { - if (!list_is_last(&xfer->transfer_list, - &spi->cur_msg->transfers)) - m_param = FRAGMENTATION; - } + mas->cur_xfer = xfer; if (m_cmd & SPI_TX_ONLY) { @@ -332,8 +354,8 @@ static void setup_fifo_xfer(struct spi_transfer *xfer, mas->rx_rem_bytes = xfer->len; } writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG); - geni_se_setup_m_cmd(se, m_cmd, m_param); - + mas->cur_mcmd = CMD_XFER; + geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION); /* * TX_WATERMARK_REG should be set after SPI configuration and * setting up GENI SE engine, as driver starts data transfer @@ -489,7 +511,11 @@ static irqreturn_t geni_spi_isr(int irq, void *data) ret = geni_spi_handle_tx(mas); if (m_irq & M_CMD_DONE_EN) { - spi_finalize_current_transfer(spi); + if (mas->cur_mcmd == CMD_XFER) + spi_finalize_current_transfer(spi); + else if (mas->cur_mcmd == CMD_CS) + complete(&mas->xfer_done); + mas->cur_mcmd = CMD_NONE; /* * If this happens, then a CMD_DONE came before all the Tx * buffer bytes were sent out. This is unusual, log this @@ -572,6 +598,7 @@ static int spi_geni_probe(struct platform_device *pdev) spi->transfer_one = spi_geni_transfer_one; spi->auto_runtime_pm = true; spi->handle_err = handle_fifo_timeout; + spi->set_cs = spi_geni_set_cs; init_completion(&mas->xfer_done); spin_lock_init(&mas->lock); -- Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
