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https://github.com/brain-hackers/u-boot-brain
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![Tom Rini](/assets/img/avatar_default.png)
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
104 lines
2.5 KiB
C
104 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* clk-synthesizer.c
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*
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* Clock synthesizer apis
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*
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* Copyright (C) 2016, Texas Instruments, Incorporated - http://www.ti.com/
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*/
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#include <common.h>
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#include <asm/arch/clk_synthesizer.h>
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#include <i2c.h>
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/**
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* clk_synthesizer_reg_read - Read register from synthesizer.
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* @addr: addr within the i2c device
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* buf: Buffer to which value is to be read.
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*
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* For reading the register from this clock synthesizer, a command needs to
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* be send along with enabling byte read more, and then read can happen.
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* Returns 0 on success
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*/
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static int clk_synthesizer_reg_read(int addr, uint8_t *buf)
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{
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int rc;
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/* Enable Bye read */
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addr = addr | CLK_SYNTHESIZER_BYTE_MODE;
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/* Send the command byte */
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rc = i2c_write(CLK_SYNTHESIZER_I2C_ADDR, addr, 1, buf, 1);
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if (rc)
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printf("Failed to send command to clock synthesizer\n");
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/* Read the Data */
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return i2c_read(CLK_SYNTHESIZER_I2C_ADDR, addr, 1, buf, 1);
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}
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/**
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* clk_synthesizer_reg_write - Write a value to register in synthesizer.
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* @addr: addr within the i2c device
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* val: Value to be written in the addr.
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*
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* Enable the byte read mode in the address and start the i2c transfer.
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* Returns 0 on success
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*/
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static int clk_synthesizer_reg_write(int addr, uint8_t val)
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{
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uint8_t cmd[2];
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int rc = 0;
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/* Enable byte write */
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cmd[0] = addr | CLK_SYNTHESIZER_BYTE_MODE;
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cmd[1] = val;
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rc = i2c_write(CLK_SYNTHESIZER_I2C_ADDR, addr, 1, cmd, 2);
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if (rc)
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printf("Clock synthesizer reg write failed at addr = 0x%x\n",
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addr);
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return rc;
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}
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/**
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* setup_clock_syntherizer - Program the clock synthesizer to get the desired
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* frequency.
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* @data: Data containing the desired output
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*
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* This is a PLL-based high performance synthesizer which gives 3 outputs
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* as per the PLL_DIV and load capacitor programmed.
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*/
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int setup_clock_synthesizer(struct clk_synth *data)
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{
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int rc;
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uint8_t val;
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rc = i2c_probe(CLK_SYNTHESIZER_I2C_ADDR);
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if (rc) {
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printf("i2c probe failed at address 0x%x\n",
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CLK_SYNTHESIZER_I2C_ADDR);
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return rc;
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}
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rc = clk_synthesizer_reg_read(CLK_SYNTHESIZER_ID_REG, &val);
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if (val != data->id)
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return rc;
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/* Crystal Load capacitor selection */
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rc = clk_synthesizer_reg_write(CLK_SYNTHESIZER_XCSEL, data->capacitor);
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if (rc)
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return rc;
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rc = clk_synthesizer_reg_write(CLK_SYNTHESIZER_MUX_REG, data->mux);
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if (rc)
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return rc;
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rc = clk_synthesizer_reg_write(CLK_SYNTHESIZER_PDIV2_REG, data->pdiv2);
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if (rc)
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return rc;
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rc = clk_synthesizer_reg_write(CLK_SYNTHESIZER_PDIV3_REG, data->pdiv3);
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if (rc)
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return rc;
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return 0;
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}
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