ASoC: OMAP4: Add support for McPDM

McPDM is the interface between Phoenix audio codec
and the OMAP4430 processor. It enables data to be transfered
to/from Phoenix at sample rates of 88.4 or 96 KHz.

Signed-off-by: Jorge Eduardo Candelaria <jorge.candelaria@ti.com>
Signed-off-by: Margarita Olaya <x0080101@ti.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 635 insertions, 0 deletions

diff --git a/sound/soc/omap/mcpdm.c b/sound/soc/omap/mcpdm.c
new file mode 100644
index 000000000000..ad8df6cfae88
--- /dev/null
+++ b/sound/soc/omap/mcpdm.c
@@ -0,0 +1,484 @@
+/*
+ * 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/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 */