/*
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* Copyright (C) 2009
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* Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <spi.h>
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#include <s6e63d6.h>
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/*
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* Each transfer is performed as:
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* 1. chip-select active
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* 2. send 8-bit start code
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* 3. send 16-bit data
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* 4. chip-select inactive
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*/
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static int send_word(struct s6e63d6 *data, u8 rs, u16 word)
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{
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/*
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* The start byte looks like (binary):
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* 01110<ID><RS><R/W>
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* RS is 0 for index or 1 for data, and R/W is 0 for write.
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*/
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u32 buf8 = 0x70 | data->id | (rs & 2);
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u32 buf16 = cpu_to_le16(word);
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u32 buf_in;
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int err;
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err = spi_xfer(data->slave, 8, &buf8, &buf_in, SPI_XFER_BEGIN);
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if (err)
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return err;
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return spi_xfer(data->slave, 16, &buf16, &buf_in, SPI_XFER_END);
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}
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/* Index and param differ in Register Select bit */
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int s6e63d6_index(struct s6e63d6 *data, u8 idx)
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{
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return send_word(data, 0, idx);
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}
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int s6e63d6_param(struct s6e63d6 *data, u16 param)
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{
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return send_word(data, 2, param);
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}
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int s6e63d6_init(struct s6e63d6 *data)
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{
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if (data->id != 0 && data->id != 4) {
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printf("s6e63d6: invalid ID %u\n", data->id);
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return 1;
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}
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data->slave = spi_setup_slave(data->bus, data->cs, 100000, SPI_MODE_3);
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if (!data->slave)
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return 1;
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return 0;
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}
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