mcpdm.c
/*
* mcpdm.c -- McPDM interface driver
*
* Author: Jorge Eduardo Candelaria <x0107209@ti.com>
* Copyright (C) 2009 - Texas Instruments, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/irq.h>
#include "mcpdm.h"
static struct omap_mcpdm *mcpdm;
static inline void omap_mcpdm_write(u16 reg, u32 val)
{
__raw_writel(val, mcpdm->io_base + reg);
}
static inline int omap_mcpdm_read(u16 reg)
{
return __raw_readl(mcpdm->io_base + reg);
}
static void omap_mcpdm_reg_dump(void)
{
dev_dbg(mcpdm->dev, "***********************\n");
dev_dbg(mcpdm->dev, "IRQSTATUS_RAW: 0x%04x\n",
omap_mcpdm_read(MCPDM_IRQSTATUS_RAW));
dev_dbg(mcpdm->dev, "IRQSTATUS: 0x%04x\n",
omap_mcpdm_read(MCPDM_IRQSTATUS));
dev_dbg(mcpdm->dev, "IRQENABLE_SET: 0x%04x\n",
omap_mcpdm_read(MCPDM_IRQENABLE_SET));
dev_dbg(mcpdm->dev, "IRQENABLE_CLR: 0x%04x\n",
omap_mcpdm_read(MCPDM_IRQENABLE_CLR));
dev_dbg(mcpdm->dev, "IRQWAKE_EN: 0x%04x\n",
omap_mcpdm_read(MCPDM_IRQWAKE_EN));
dev_dbg(mcpdm->dev, "DMAENABLE_SET: 0x%04x\n",
omap_mcpdm_read(MCPDM_DMAENABLE_SET));
dev_dbg(mcpdm->dev, "DMAENABLE_CLR: 0x%04x\n",
omap_mcpdm_read(MCPDM_DMAENABLE_CLR));
dev_dbg(mcpdm->dev, "DMAWAKEEN: 0x%04x\n",
omap_mcpdm_read(MCPDM_DMAWAKEEN));
dev_dbg(mcpdm->dev, "CTRL: 0x%04x\n",
omap_mcpdm_read(MCPDM_CTRL));
dev_dbg(mcpdm->dev, "DN_DATA: 0x%04x\n",
omap_mcpdm_read(MCPDM_DN_DATA));
dev_dbg(mcpdm->dev, "UP_DATA: 0x%04x\n",
omap_mcpdm_read(MCPDM_UP_DATA));
dev_dbg(mcpdm->dev, "FIFO_CTRL_DN: 0x%04x\n",
omap_mcpdm_read(MCPDM_FIFO_CTRL_DN));
dev_dbg(mcpdm->dev, "FIFO_CTRL_UP: 0x%04x\n",
omap_mcpdm_read(MCPDM_FIFO_CTRL_UP));
dev_dbg(mcpdm->dev, "DN_OFFSET: 0x%04x\n",
omap_mcpdm_read(MCPDM_DN_OFFSET));
dev_dbg(mcpdm->dev, "***********************\n");
}
/*
* Takes the McPDM module in and out of reset state.
* Uplink and downlink can be reset individually.
*/
static void omap_mcpdm_reset_capture(int reset)
{
int ctrl = omap_mcpdm_read(MCPDM_CTRL);
if (reset)
ctrl |= SW_UP_RST;
else
ctrl &= ~SW_UP_RST;
omap_mcpdm_write(MCPDM_CTRL, ctrl);
}
static void omap_mcpdm_reset_playback(int reset)
{
int ctrl = omap_mcpdm_read(MCPDM_CTRL);
if (reset)
ctrl |= SW_DN_RST;
else
ctrl &= ~SW_DN_RST;
omap_mcpdm_write(MCPDM_CTRL, ctrl);
}
/*
* Enables the transfer through the PDM interface to/from the Phoenix
* codec by enabling the corresponding UP or DN channels.
*/
void omap_mcpdm_start(int stream)
{
int ctrl = omap_mcpdm_read(MCPDM_CTRL);
if (stream)
ctrl |= mcpdm->up_channels;
else
ctrl |= mcpdm->dn_channels;
omap_mcpdm_write(MCPDM_CTRL, ctrl);
}
/*
* Disables the transfer through the PDM interface to/from the Phoenix
* codec by disabling the corresponding UP or DN channels.
*/
void omap_mcpdm_stop(int stream)
{
int ctrl = omap_mcpdm_read(MCPDM_CTRL);
if (stream)
ctrl &= ~mcpdm->up_channels;
else
ctrl &= ~mcpdm->dn_channels;
omap_mcpdm_write(MCPDM_CTRL, ctrl);
}
/*
* Configures McPDM uplink for audio recording.
* This function should be called before omap_mcpdm_start.
*/
int omap_mcpdm_capture_open(struct omap_mcpdm_link *uplink)
{
int irq_mask = 0;
int ctrl;
if (!uplink)
return -EINVAL;
mcpdm->uplink = uplink;
/* Enable irq request generation */
irq_mask |= uplink->irq_mask & MCPDM_UPLINK_IRQ_MASK;
omap_mcpdm_write(MCPDM_IRQENABLE_SET, irq_mask);
/* Configure uplink threshold */
if (uplink->threshold > UP_THRES_MAX)
uplink->threshold = UP_THRES_MAX;
omap_mcpdm_write(MCPDM_FIFO_CTRL_UP, uplink->threshold);
/* Configure DMA controller */
omap_mcpdm_write(MCPDM_DMAENABLE_SET, DMA_UP_ENABLE);
/* Set pdm out format */
ctrl = omap_mcpdm_read(MCPDM_CTRL);
ctrl &= ~PDMOUTFORMAT;
ctrl |= uplink->format & PDMOUTFORMAT;
/* Uplink channels */
mcpdm->up_channels = uplink->channels & (PDM_UP_MASK | PDM_STATUS_MASK);
omap_mcpdm_write(MCPDM_CTRL, ctrl);
return 0;
}
/*
* Configures McPDM downlink for audio playback.
* This function should be called before omap_mcpdm_start.
*/
int omap_mcpdm_playback_open(struct omap_mcpdm_link *downlink)
{
int irq_mask = 0;
int ctrl;
if (!downlink)
return -EINVAL;
mcpdm->downlink = downlink;
/* Enable irq request generation */
irq_mask |= downlink->irq_mask & MCPDM_DOWNLINK_IRQ_MASK;
omap_mcpdm_write(MCPDM_IRQENABLE_SET, irq_mask);
/* Configure uplink threshold */
if (downlink->threshold > DN_THRES_MAX)
downlink->threshold = DN_THRES_MAX;
omap_mcpdm_write(MCPDM_FIFO_CTRL_DN, downlink->threshold);
/* Enable DMA request generation */
omap_mcpdm_write(MCPDM_DMAENABLE_SET, DMA_DN_ENABLE);
/* Set pdm out format */
ctrl = omap_mcpdm_read(MCPDM_CTRL);
ctrl &= ~PDMOUTFORMAT;
ctrl |= downlink->format & PDMOUTFORMAT;
/* Downlink channels */
mcpdm->dn_channels = downlink->channels & (PDM_DN_MASK | PDM_CMD_MASK);
omap_mcpdm_write(MCPDM_CTRL, ctrl);
return 0;
}
/*
* Cleans McPDM uplink configuration.
* This function should be called when the stream is closed.
*/
int omap_mcpdm_capture_close(struct omap_mcpdm_link *uplink)
{
int irq_mask = 0;
if (!uplink)
return -EINVAL;
/* Disable irq request generation */
irq_mask |= uplink->irq_mask & MCPDM_UPLINK_IRQ_MASK;
omap_mcpdm_write(MCPDM_IRQENABLE_CLR, irq_mask);
/* Disable DMA request generation */
omap_mcpdm_write(MCPDM_DMAENABLE_CLR, DMA_UP_ENABLE);
/* Clear Downlink channels */
mcpdm->up_channels = 0;
mcpdm->uplink = NULL;
return 0;
}
/*
* Cleans McPDM downlink configuration.
* This function should be called when the stream is closed.
*/
int omap_mcpdm_playback_close(struct omap_mcpdm_link *downlink)
{
int irq_mask = 0;
if (!downlink)
return -EINVAL;
/* Disable irq request generation */
irq_mask |= downlink->irq_mask & MCPDM_DOWNLINK_IRQ_MASK;
omap_mcpdm_write(MCPDM_IRQENABLE_CLR, irq_mask);
/* Disable DMA request generation */
omap_mcpdm_write(MCPDM_DMAENABLE_CLR, DMA_DN_ENABLE);
/* clear Downlink channels */
mcpdm->dn_channels = 0;
mcpdm->downlink = NULL;
return 0;
}
static irqreturn_t omap_mcpdm_irq_handler(int irq, void *dev_id)
{
struct omap_mcpdm *mcpdm_irq = dev_id;
int irq_status;
irq_status = omap_mcpdm_read(MCPDM_IRQSTATUS);
/* Acknowledge irq event */
omap_mcpdm_write(MCPDM_IRQSTATUS, irq_status);
if (irq & MCPDM_DN_IRQ_FULL) {
dev_err(mcpdm_irq->dev, "DN FIFO error %x\n", irq_status);
omap_mcpdm_reset_playback(1);
omap_mcpdm_playback_open(mcpdm_irq->downlink);
omap_mcpdm_reset_playback(0);
}
if (irq & MCPDM_DN_IRQ_EMPTY) {
dev_err(mcpdm_irq->dev, "DN FIFO error %x\n", irq_status);
omap_mcpdm_reset_playback(1);
omap_mcpdm_playback_open(mcpdm_irq->downlink);
omap_mcpdm_reset_playback(0);
}
if (irq & MCPDM_DN_IRQ) {
dev_dbg(mcpdm_irq->dev, "DN write request\n");
}
if (irq & MCPDM_UP_IRQ_FULL) {
dev_err(mcpdm_irq->dev, "UP FIFO error %x\n", irq_status);
omap_mcpdm_reset_capture(1);
omap_mcpdm_capture_open(mcpdm_irq->uplink);
omap_mcpdm_reset_capture(0);
}
if (irq & MCPDM_UP_IRQ_EMPTY) {
dev_err(mcpdm_irq->dev, "UP FIFO error %x\n", irq_status);
omap_mcpdm_reset_capture(1);
omap_mcpdm_capture_open(mcpdm_irq->uplink);
omap_mcpdm_reset_capture(0);
}
if (irq & MCPDM_UP_IRQ) {
dev_dbg(mcpdm_irq->dev, "UP write request\n");
}
return IRQ_HANDLED;
}
int omap_mcpdm_request(void)
{
int ret;
clk_enable(mcpdm->clk);
spin_lock(&mcpdm->lock);
if (!mcpdm->free) {
dev_err(mcpdm->dev, "McPDM interface is in use\n");
spin_unlock(&mcpdm->lock);
ret = -EBUSY;
goto err;
}
mcpdm->free = 0;
spin_unlock(&mcpdm->lock);
/* Disable lines while request is ongoing */
omap_mcpdm_write(MCPDM_CTRL, 0x00);
ret = request_irq(mcpdm->irq, omap_mcpdm_irq_handler,
0, "McPDM", (void *)mcpdm);
if (ret) {
dev_err(mcpdm->dev, "Request for McPDM IRQ failed\n");
goto err;
}
return 0;
err:
clk_disable(mcpdm->clk);
return ret;
}
void omap_mcpdm_free(void)
{
spin_lock(&mcpdm->lock);
if (mcpdm->free) {
dev_err(mcpdm->dev, "McPDM interface is already free\n");
spin_unlock(&mcpdm->lock);
return;
}
mcpdm->free = 1;
spin_unlock(&mcpdm->lock);
clk_disable(mcpdm->clk);
free_irq(mcpdm->irq, (void *)mcpdm);
}
/* Enable/disable DC offset cancelation for the analog
* headset path (PDM channels 1 and 2).
*/
int omap_mcpdm_set_offset(int offset1, int offset2)
{
int offset;
if ((offset1 > DN_OFST_MAX) || (offset2 > DN_OFST_MAX))
return -EINVAL;
offset = (offset1 << DN_OFST_RX1) | (offset2 << DN_OFST_RX2);
/* offset cancellation for channel 1 */
if (offset1)
offset |= DN_OFST_RX1_EN;
else
offset &= ~DN_OFST_RX1_EN;
/* offset cancellation for channel 2 */
if (offset2)
offset |= DN_OFST_RX2_EN;
else
offset &= ~DN_OFST_RX2_EN;
omap_mcpdm_write(MCPDM_DN_OFFSET, offset);
return 0;
}
int __devinit omap_mcpdm_probe(struct platform_device *pdev)
{
struct resource *res;
int ret = 0;
mcpdm = kzalloc(sizeof(struct omap_mcpdm), GFP_KERNEL);
if (!mcpdm) {
ret = -ENOMEM;
goto exit;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "no resource\n");
goto err_resource;
}
spin_lock_init(&mcpdm->lock);
mcpdm->free = 1;
mcpdm->io_base = ioremap(res->start, resource_size(res));
if (!mcpdm->io_base) {
ret = -ENOMEM;
goto err_resource;
}
mcpdm->irq = platform_get_irq(pdev, 0);
mcpdm->clk = clk_get(&pdev->dev, "pdm_ck");
if (IS_ERR(mcpdm->clk)) {
ret = PTR_ERR(mcpdm->clk);
dev_err(&pdev->dev, "unable to get pdm_ck: %d\n", ret);
goto err_clk;
}
mcpdm->dev = &pdev->dev;
platform_set_drvdata(pdev, mcpdm);
return 0;
err_clk:
iounmap(mcpdm->io_base);
err_resource:
kfree(mcpdm);
exit:
return ret;
}
int __devexit omap_mcpdm_remove(struct platform_device *pdev)
{
struct omap_mcpdm *mcpdm_ptr = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
clk_put(mcpdm_ptr->clk);
iounmap(mcpdm_ptr->io_base);
mcpdm_ptr->clk = NULL;
mcpdm_ptr->free = 0;
mcpdm_ptr->dev = NULL;
kfree(mcpdm_ptr);
return 0;
}
