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1// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause2/*3 * Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc.4 * Copyright (c) 2014, I2SE GmbH5 */6 7/* This module implements the Qualcomm Atheros SPI protocol for8 * kernel-based SPI device.9 */10 11#include <linux/kernel.h>12#include <linux/netdevice.h>13#include <linux/spi/spi.h>14 15#include "qca_7k.h"16 17void18qcaspi_spi_error(struct qcaspi *qca)19{20 if (qca->sync != QCASPI_SYNC_READY)21 return;22 23 netdev_err(qca->net_dev, "spi error\n");24 qca->sync = QCASPI_SYNC_UNKNOWN;25 qca->stats.spi_err++;26}27 28int29qcaspi_read_register(struct qcaspi *qca, u16 reg, u16 *result)30{31 __be16 rx_data;32 __be16 tx_data;33 struct spi_transfer transfer[2];34 struct spi_message msg;35 int ret;36 37 memset(transfer, 0, sizeof(transfer));38 39 spi_message_init(&msg);40 41 tx_data = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_INTERNAL | reg);42 *result = 0;43 44 transfer[0].tx_buf = &tx_data;45 transfer[0].len = QCASPI_CMD_LEN;46 transfer[1].rx_buf = &rx_data;47 transfer[1].len = QCASPI_CMD_LEN;48 49 spi_message_add_tail(&transfer[0], &msg);50 51 if (qca->legacy_mode) {52 spi_sync(qca->spi_dev, &msg);53 spi_message_init(&msg);54 }55 spi_message_add_tail(&transfer[1], &msg);56 ret = spi_sync(qca->spi_dev, &msg);57 58 if (!ret)59 ret = msg.status;60 61 if (ret)62 qcaspi_spi_error(qca);63 else64 *result = be16_to_cpu(rx_data);65 66 return ret;67}68 69static int70__qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value)71{72 __be16 tx_data[2];73 struct spi_transfer transfer[2];74 struct spi_message msg;75 int ret;76 77 memset(&transfer, 0, sizeof(transfer));78 79 spi_message_init(&msg);80 81 tx_data[0] = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_INTERNAL | reg);82 tx_data[1] = cpu_to_be16(value);83 84 transfer[0].tx_buf = &tx_data[0];85 transfer[0].len = QCASPI_CMD_LEN;86 transfer[1].tx_buf = &tx_data[1];87 transfer[1].len = QCASPI_CMD_LEN;88 89 spi_message_add_tail(&transfer[0], &msg);90 if (qca->legacy_mode) {91 spi_sync(qca->spi_dev, &msg);92 spi_message_init(&msg);93 }94 spi_message_add_tail(&transfer[1], &msg);95 ret = spi_sync(qca->spi_dev, &msg);96 97 if (!ret)98 ret = msg.status;99 100 if (ret)101 qcaspi_spi_error(qca);102 103 return ret;104}105 106int107qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value, int retry)108{109 int ret, i = 0;110 u16 confirmed;111 112 do {113 ret = __qcaspi_write_register(qca, reg, value);114 if (ret)115 return ret;116 117 if (!retry)118 return 0;119 120 ret = qcaspi_read_register(qca, reg, &confirmed);121 if (ret)122 return ret;123 124 ret = confirmed != value;125 if (!ret)126 return 0;127 128 i++;129 qca->stats.write_verify_failed++;130 131 } while (i <= retry);132 133 return ret;134}135