ASoC: Add a new imx-ssi sound driver
The old driver has the number of SSI units in the system hardcoded,
does not make use of the device model and works only on i.MX21/27.
This driver replaces it. It works in DMA mode on i.MX21/27 and using
an FIQ handler on other systems. It also supports AC97 mode of
the SSI units.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Javier Martin <javier.martin@vista-silicon.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/arch/arm/plat-mxc/ssi-fiq.S b/arch/arm/plat-mxc/ssi-fiq.S
new file mode 100644
index 0000000..4ddce56
--- /dev/null
+++ b/arch/arm/plat-mxc/ssi-fiq.S
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2009 Sascha Hauer <s.hauer@pengutronix.de>
+ *
+ * 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.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * r8 = bit 0-15: tx offset, bit 16-31: tx buffer size
+ * r9 = bit 0-15: rx offset, bit 16-31: rx buffer size
+ */
+
+#define SSI_STX0 0x00
+#define SSI_SRX0 0x08
+#define SSI_SISR 0x14
+#define SSI_SIER 0x18
+#define SSI_SACNT 0x38
+
+#define SSI_SACNT_AC97EN (1 << 0)
+
+#define SSI_SIER_TFE0_EN (1 << 0)
+#define SSI_SISR_TFE0 (1 << 0)
+#define SSI_SISR_RFF0 (1 << 2)
+#define SSI_SIER_RFF0_EN (1 << 2)
+
+ .text
+ .global imx_ssi_fiq_start
+ .global imx_ssi_fiq_end
+ .global imx_ssi_fiq_base
+ .global imx_ssi_fiq_rx_buffer
+ .global imx_ssi_fiq_tx_buffer
+
+imx_ssi_fiq_start:
+ ldr r12, imx_ssi_fiq_base
+
+ /* TX */
+ ldr r11, imx_ssi_fiq_tx_buffer
+
+ /* shall we send? */
+ ldr r13, [r12, #SSI_SIER]
+ tst r13, #SSI_SIER_TFE0_EN
+ beq 1f
+
+ /* TX FIFO empty? */
+ ldr r13, [r12, #SSI_SISR]
+ tst r13, #SSI_SISR_TFE0
+ beq 1f
+
+ mov r10, #0x10000
+ sub r10, #1
+ and r10, r10, r8 /* r10: current buffer offset */
+
+ add r11, r11, r10
+
+ ldrh r13, [r11]
+ strh r13, [r12, #SSI_STX0]
+
+ ldrh r13, [r11, #2]
+ strh r13, [r12, #SSI_STX0]
+
+ ldrh r13, [r11, #4]
+ strh r13, [r12, #SSI_STX0]
+
+ ldrh r13, [r11, #6]
+ strh r13, [r12, #SSI_STX0]
+
+ add r10, #8
+ lsr r13, r8, #16 /* r13: buffer size */
+ cmp r10, r13
+ lslgt r8, r13, #16
+ addle r8, #8
+1:
+ /* RX */
+
+ /* shall we receive? */
+ ldr r13, [r12, #SSI_SIER]
+ tst r13, #SSI_SIER_RFF0_EN
+ beq 1f
+
+ /* RX FIFO full? */
+ ldr r13, [r12, #SSI_SISR]
+ tst r13, #SSI_SISR_RFF0
+ beq 1f
+
+ ldr r11, imx_ssi_fiq_rx_buffer
+
+ mov r10, #0x10000
+ sub r10, #1
+ and r10, r10, r9 /* r10: current buffer offset */
+
+ add r11, r11, r10
+
+ ldr r13, [r12, #SSI_SACNT]
+ tst r13, #SSI_SACNT_AC97EN
+
+ ldr r13, [r12, #SSI_SRX0]
+ strh r13, [r11]
+
+ ldr r13, [r12, #SSI_SRX0]
+ strh r13, [r11, #2]
+
+ /* dummy read to skip slot 12 */
+ ldrne r13, [r12, #SSI_SRX0]
+
+ ldr r13, [r12, #SSI_SRX0]
+ strh r13, [r11, #4]
+
+ ldr r13, [r12, #SSI_SRX0]
+ strh r13, [r11, #6]
+
+ /* dummy read to skip slot 12 */
+ ldrne r13, [r12, #SSI_SRX0]
+
+ add r10, #8
+ lsr r13, r9, #16 /* r13: buffer size */
+ cmp r10, r13
+ lslgt r9, r13, #16
+ addle r9, #8
+
+1:
+ @ return from FIQ
+ subs pc, lr, #4
+imx_ssi_fiq_base:
+ .word 0x0
+imx_ssi_fiq_rx_buffer:
+ .word 0x0
+imx_ssi_fiq_tx_buffer:
+ .word 0x0
+imx_ssi_fiq_end:
+