diff options
author | Sascha Hauer <s.hauer@pengutronix.de> | 2009-11-25 16:41:04 +0100 |
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committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2010-01-17 11:09:46 +0000 |
commit | 8380222ec9458d38a4e0cc3cb688ad7fff311df4 (patch) | |
tree | db2774ff28b93f437bcf217f1b10337a8d4fd9b5 /arch/arm/plat-mxc/ssi-fiq.S | |
parent | 53242c68333570631a15a69842851b458eca3d99 (diff) |
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>
Diffstat (limited to 'arch/arm/plat-mxc/ssi-fiq.S')
-rw-r--r-- | arch/arm/plat-mxc/ssi-fiq.S | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/arch/arm/plat-mxc/ssi-fiq.S b/arch/arm/plat-mxc/ssi-fiq.S new file mode 100644 index 00000000000..4ddce565b35 --- /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: + |