1 From b257baf20b44e97770a2654a07f196fcbcd46e92 Mon Sep 17 00:00:00 2001
2 From: John Crispin <blogic@openwrt.org>
3 Date: Mon, 10 Oct 2011 22:29:13 +0200
4 Subject: [PATCH 42/70] SPI: MIPS: lantiq: adds spi xway
7 .../mips/include/asm/mach-lantiq/lantiq_platform.h | 9 +
8 .../mips/include/asm/mach-lantiq/xway/lantiq_irq.h | 2 +
9 drivers/spi/Kconfig | 8 +
10 drivers/spi/Makefile | 1 +
11 drivers/spi/spi-xway.c | 1068 ++++++++++++++++++++
12 5 files changed, 1088 insertions(+), 0 deletions(-)
13 create mode 100644 drivers/spi/spi-xway.c
15 --- a/arch/mips/include/asm/mach-lantiq/lantiq_platform.h
16 +++ b/arch/mips/include/asm/mach-lantiq/lantiq_platform.h
17 @@ -50,4 +50,13 @@ struct ltq_eth_data {
22 +struct ltq_spi_platform_data {
26 +struct ltq_spi_controller_data {
31 --- a/arch/mips/include/asm/mach-lantiq/xway/lantiq_irq.h
32 +++ b/arch/mips/include/asm/mach-lantiq/xway/lantiq_irq.h
35 #define LTQ_SSC_TIR (INT_NUM_IM0_IRL0 + 15)
36 #define LTQ_SSC_RIR (INT_NUM_IM0_IRL0 + 14)
37 +#define LTQ_SSC_TIR_AR9 (INT_NUM_IM0_IRL0 + 14)
38 +#define LTQ_SSC_RIR_AR9 (INT_NUM_IM0_IRL0 + 15)
39 #define LTQ_SSC_EIR (INT_NUM_IM0_IRL0 + 16)
41 #define LTQ_MEI_DYING_GASP_INT (INT_NUM_IM1_IRL0 + 21)
42 --- a/drivers/spi/Kconfig
43 +++ b/drivers/spi/Kconfig
44 @@ -393,6 +393,14 @@ config SPI_NUC900
46 SPI driver for Nuvoton NUC900 series ARM SoCs
49 + tristate "Lantiq XWAY SPI controller"
50 + depends on LANTIQ && SOC_TYPE_XWAY
53 + This driver supports the Lantiq SoC SPI controller in master
57 # Add new SPI master controllers in alphabetical order above this line
59 --- a/drivers/spi/Makefile
60 +++ b/drivers/spi/Makefile
61 @@ -60,4 +60,5 @@ obj-$(CONFIG_SPI_TLE62X0) += spi-tle62x
62 obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o
63 obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
64 obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
65 +obj-$(CONFIG_SPI_XWAY) += spi-xway.o
68 +++ b/drivers/spi/spi-xway.c
71 + * Lantiq SoC SPI controller
73 + * Copyright (C) 2011 Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
75 + * This program is free software; you can distribute it and/or modify it
76 + * under the terms of the GNU General Public License (Version 2) as
77 + * published by the Free Software Foundation.
80 +#include <linux/init.h>
81 +#include <linux/module.h>
82 +#include <linux/workqueue.h>
83 +#include <linux/platform_device.h>
84 +#include <linux/io.h>
85 +#include <linux/sched.h>
86 +#include <linux/delay.h>
87 +#include <linux/interrupt.h>
88 +#include <linux/completion.h>
89 +#include <linux/spinlock.h>
90 +#include <linux/err.h>
91 +#include <linux/clk.h>
92 +#include <linux/gpio.h>
93 +#include <linux/spi/spi.h>
94 +#include <linux/spi/spi_bitbang.h>
96 +#include <lantiq_soc.h>
97 +#include <lantiq_platform.h>
99 +#define LTQ_SPI_CLC 0x00 /* Clock control */
100 +#define LTQ_SPI_PISEL 0x04 /* Port input select */
101 +#define LTQ_SPI_ID 0x08 /* Identification */
102 +#define LTQ_SPI_CON 0x10 /* Control */
103 +#define LTQ_SPI_STAT 0x14 /* Status */
104 +#define LTQ_SPI_WHBSTATE 0x18 /* Write HW modified state */
105 +#define LTQ_SPI_TB 0x20 /* Transmit buffer */
106 +#define LTQ_SPI_RB 0x24 /* Receive buffer */
107 +#define LTQ_SPI_RXFCON 0x30 /* Receive FIFO control */
108 +#define LTQ_SPI_TXFCON 0x34 /* Transmit FIFO control */
109 +#define LTQ_SPI_FSTAT 0x38 /* FIFO status */
110 +#define LTQ_SPI_BRT 0x40 /* Baudrate timer */
111 +#define LTQ_SPI_BRSTAT 0x44 /* Baudrate timer status */
112 +#define LTQ_SPI_SFCON 0x60 /* Serial frame control */
113 +#define LTQ_SPI_SFSTAT 0x64 /* Serial frame status */
114 +#define LTQ_SPI_GPOCON 0x70 /* General purpose output control */
115 +#define LTQ_SPI_GPOSTAT 0x74 /* General purpose output status */
116 +#define LTQ_SPI_FGPO 0x78 /* Forced general purpose output */
117 +#define LTQ_SPI_RXREQ 0x80 /* Receive request */
118 +#define LTQ_SPI_RXCNT 0x84 /* Receive count */
119 +#define LTQ_SPI_DMACON 0xEC /* DMA control */
120 +#define LTQ_SPI_IRNEN 0xF4 /* Interrupt node enable */
121 +#define LTQ_SPI_IRNICR 0xF8 /* Interrupt node interrupt capture */
122 +#define LTQ_SPI_IRNCR 0xFC /* Interrupt node control */
124 +#define LTQ_SPI_CLC_SMC_SHIFT 16 /* Clock divider for sleep mode */
125 +#define LTQ_SPI_CLC_SMC_MASK 0xFF
126 +#define LTQ_SPI_CLC_RMC_SHIFT 8 /* Clock divider for normal run mode */
127 +#define LTQ_SPI_CLC_RMC_MASK 0xFF
128 +#define LTQ_SPI_CLC_DISS BIT(1) /* Disable status bit */
129 +#define LTQ_SPI_CLC_DISR BIT(0) /* Disable request bit */
131 +#define LTQ_SPI_ID_TXFS_SHIFT 24 /* Implemented TX FIFO size */
132 +#define LTQ_SPI_ID_TXFS_MASK 0x3F
133 +#define LTQ_SPI_ID_RXFS_SHIFT 16 /* Implemented RX FIFO size */
134 +#define LTQ_SPI_ID_RXFS_MASK 0x3F
135 +#define LTQ_SPI_ID_REV_MASK 0x1F /* Hardware revision number */
136 +#define LTQ_SPI_ID_CFG BIT(5) /* DMA interface support */
138 +#define LTQ_SPI_CON_BM_SHIFT 16 /* Data width selection */
139 +#define LTQ_SPI_CON_BM_MASK 0x1F
140 +#define LTQ_SPI_CON_EM BIT(24) /* Echo mode */
141 +#define LTQ_SPI_CON_IDLE BIT(23) /* Idle bit value */
142 +#define LTQ_SPI_CON_ENBV BIT(22) /* Enable byte valid control */
143 +#define LTQ_SPI_CON_RUEN BIT(12) /* Receive underflow error enable */
144 +#define LTQ_SPI_CON_TUEN BIT(11) /* Transmit underflow error enable */
145 +#define LTQ_SPI_CON_AEN BIT(10) /* Abort error enable */
146 +#define LTQ_SPI_CON_REN BIT(9) /* Receive overflow error enable */
147 +#define LTQ_SPI_CON_TEN BIT(8) /* Transmit overflow error enable */
148 +#define LTQ_SPI_CON_LB BIT(7) /* Loopback control */
149 +#define LTQ_SPI_CON_PO BIT(6) /* Clock polarity control */
150 +#define LTQ_SPI_CON_PH BIT(5) /* Clock phase control */
151 +#define LTQ_SPI_CON_HB BIT(4) /* Heading control */
152 +#define LTQ_SPI_CON_RXOFF BIT(1) /* Switch receiver off */
153 +#define LTQ_SPI_CON_TXOFF BIT(0) /* Switch transmitter off */
155 +#define LTQ_SPI_STAT_RXBV_MASK 0x7
156 +#define LTQ_SPI_STAT_RXBV_SHIFT 28
157 +#define LTQ_SPI_STAT_BSY BIT(13) /* Busy flag */
158 +#define LTQ_SPI_STAT_RUE BIT(12) /* Receive underflow error flag */
159 +#define LTQ_SPI_STAT_TUE BIT(11) /* Transmit underflow error flag */
160 +#define LTQ_SPI_STAT_AE BIT(10) /* Abort error flag */
161 +#define LTQ_SPI_STAT_RE BIT(9) /* Receive error flag */
162 +#define LTQ_SPI_STAT_TE BIT(8) /* Transmit error flag */
163 +#define LTQ_SPI_STAT_MS BIT(1) /* Master/slave select bit */
164 +#define LTQ_SPI_STAT_EN BIT(0) /* Enable bit */
166 +#define LTQ_SPI_WHBSTATE_SETTUE BIT(15) /* Set transmit underflow error flag */
167 +#define LTQ_SPI_WHBSTATE_SETAE BIT(14) /* Set abort error flag */
168 +#define LTQ_SPI_WHBSTATE_SETRE BIT(13) /* Set receive error flag */
169 +#define LTQ_SPI_WHBSTATE_SETTE BIT(12) /* Set transmit error flag */
170 +#define LTQ_SPI_WHBSTATE_CLRTUE BIT(11) /* Clear transmit underflow error flag */
171 +#define LTQ_SPI_WHBSTATE_CLRAE BIT(10) /* Clear abort error flag */
172 +#define LTQ_SPI_WHBSTATE_CLRRE BIT(9) /* Clear receive error flag */
173 +#define LTQ_SPI_WHBSTATE_CLRTE BIT(8) /* Clear transmit error flag */
174 +#define LTQ_SPI_WHBSTATE_SETME BIT(7) /* Set mode error flag */
175 +#define LTQ_SPI_WHBSTATE_CLRME BIT(6) /* Clear mode error flag */
176 +#define LTQ_SPI_WHBSTATE_SETRUE BIT(5) /* Set receive underflow error flag */
177 +#define LTQ_SPI_WHBSTATE_CLRRUE BIT(4) /* Clear receive underflow error flag */
178 +#define LTQ_SPI_WHBSTATE_SETMS BIT(3) /* Set master select bit */
179 +#define LTQ_SPI_WHBSTATE_CLRMS BIT(2) /* Clear master select bit */
180 +#define LTQ_SPI_WHBSTATE_SETEN BIT(1) /* Set enable bit (operational mode) */
181 +#define LTQ_SPI_WHBSTATE_CLREN BIT(0) /* Clear enable bit (config mode */
182 +#define LTQ_SPI_WHBSTATE_CLR_ERRORS 0x0F50
184 +#define LTQ_SPI_RXFCON_RXFITL_SHIFT 8 /* FIFO interrupt trigger level */
185 +#define LTQ_SPI_RXFCON_RXFITL_MASK 0x3F
186 +#define LTQ_SPI_RXFCON_RXFLU BIT(1) /* FIFO flush */
187 +#define LTQ_SPI_RXFCON_RXFEN BIT(0) /* FIFO enable */
189 +#define LTQ_SPI_TXFCON_TXFITL_SHIFT 8 /* FIFO interrupt trigger level */
190 +#define LTQ_SPI_TXFCON_TXFITL_MASK 0x3F
191 +#define LTQ_SPI_TXFCON_TXFLU BIT(1) /* FIFO flush */
192 +#define LTQ_SPI_TXFCON_TXFEN BIT(0) /* FIFO enable */
194 +#define LTQ_SPI_FSTAT_RXFFL_MASK 0x3f
195 +#define LTQ_SPI_FSTAT_RXFFL_SHIFT 0
196 +#define LTQ_SPI_FSTAT_TXFFL_MASK 0x3f
197 +#define LTQ_SPI_FSTAT_TXFFL_SHIFT 8
199 +#define LTQ_SPI_GPOCON_ISCSBN_SHIFT 8
200 +#define LTQ_SPI_GPOCON_INVOUTN_SHIFT 0
202 +#define LTQ_SPI_FGPO_SETOUTN_SHIFT 8
203 +#define LTQ_SPI_FGPO_CLROUTN_SHIFT 0
205 +#define LTQ_SPI_RXREQ_RXCNT_MASK 0xFFFF /* Receive count value */
206 +#define LTQ_SPI_RXCNT_TODO_MASK 0xFFFF /* Recevie to-do value */
208 +#define LTQ_SPI_IRNEN_F BIT(3) /* Frame end interrupt request */
209 +#define LTQ_SPI_IRNEN_E BIT(2) /* Error end interrupt request */
210 +#define LTQ_SPI_IRNEN_T BIT(1) /* Transmit end interrupt request */
211 +#define LTQ_SPI_IRNEN_R BIT(0) /* Receive end interrupt request */
212 +#define LTQ_SPI_IRNEN_ALL 0xF
214 +/* Hard-wired GPIOs used by SPI controller */
215 +#define LTQ_SPI_GPIO_DI 16
216 +#define LTQ_SPI_GPIO_DO 17
217 +#define LTQ_SPI_GPIO_CLK 18
220 + struct spi_bitbang bitbang;
221 + struct completion done;
224 + struct device *dev;
225 + void __iomem *base;
226 + struct clk *fpiclk;
227 + struct clk *spiclk;
237 + struct spi_transfer *curr_transfer;
239 + u32 (*get_tx) (struct ltq_spi *);
243 + unsigned dma_support:1;
244 + unsigned cfg_mode:1;
248 +struct ltq_spi_controller_state {
249 + void (*cs_activate) (struct spi_device *);
250 + void (*cs_deactivate) (struct spi_device *);
253 +struct ltq_spi_irq_map {
255 + irq_handler_t handler;
258 +struct ltq_spi_cs_gpio_map {
263 +static inline struct ltq_spi *ltq_spi_to_hw(struct spi_device *spi)
265 + return spi_master_get_devdata(spi->master);
268 +static inline u32 ltq_spi_reg_read(struct ltq_spi *hw, u32 reg)
270 + return ioread32be(hw->base + reg);
273 +static inline void ltq_spi_reg_write(struct ltq_spi *hw, u32 val, u32 reg)
275 + iowrite32be(val, hw->base + reg);
278 +static inline void ltq_spi_reg_setbit(struct ltq_spi *hw, u32 bits, u32 reg)
282 + val = ltq_spi_reg_read(hw, reg);
284 + ltq_spi_reg_write(hw, val, reg);
287 +static inline void ltq_spi_reg_clearbit(struct ltq_spi *hw, u32 bits, u32 reg)
291 + val = ltq_spi_reg_read(hw, reg);
293 + ltq_spi_reg_write(hw, val, reg);
296 +static void ltq_spi_hw_enable(struct ltq_spi *hw)
300 + /* Power-up mdule */
301 + clk_enable(hw->spiclk);
304 + * Set clock divider for run mode to 1 to
305 + * run at same frequency as FPI bus
307 + clc = (1 << LTQ_SPI_CLC_RMC_SHIFT);
308 + ltq_spi_reg_write(hw, clc, LTQ_SPI_CLC);
311 +static void ltq_spi_hw_disable(struct ltq_spi *hw)
313 + /* Set clock divider to 0 and set module disable bit */
314 + ltq_spi_reg_write(hw, LTQ_SPI_CLC_DISS, LTQ_SPI_CLC);
316 + /* Power-down mdule */
317 + clk_disable(hw->spiclk);
320 +static void ltq_spi_reset_fifos(struct ltq_spi *hw)
325 + * Enable and flush FIFOs. Set interrupt trigger level to
326 + * half of FIFO count implemented in hardware.
328 + if (hw->txfs > 1) {
329 + val = hw->txfs << (LTQ_SPI_TXFCON_TXFITL_SHIFT - 1);
330 + val |= LTQ_SPI_TXFCON_TXFEN | LTQ_SPI_TXFCON_TXFLU;
331 + ltq_spi_reg_write(hw, val, LTQ_SPI_TXFCON);
334 + if (hw->rxfs > 1) {
335 + val = hw->rxfs << (LTQ_SPI_RXFCON_RXFITL_SHIFT - 1);
336 + val |= LTQ_SPI_RXFCON_RXFEN | LTQ_SPI_RXFCON_RXFLU;
337 + ltq_spi_reg_write(hw, val, LTQ_SPI_RXFCON);
341 +static inline int ltq_spi_wait_ready(struct ltq_spi *hw)
344 + unsigned long timeout;
346 + timeout = jiffies + msecs_to_jiffies(200);
349 + stat = ltq_spi_reg_read(hw, LTQ_SPI_STAT);
350 + if (!(stat & LTQ_SPI_STAT_BSY))
354 + } while (!time_after_eq(jiffies, timeout));
356 + dev_err(hw->dev, "SPI wait ready timed out\n");
361 +static void ltq_spi_config_mode_set(struct ltq_spi *hw)
367 + * Putting the SPI module in config mode is only safe if no
368 + * transfer is in progress as indicated by busy flag STATE.BSY.
370 + if (ltq_spi_wait_ready(hw)) {
371 + ltq_spi_reset_fifos(hw);
372 + hw->status = -ETIMEDOUT;
374 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLREN, LTQ_SPI_WHBSTATE);
379 +static void ltq_spi_run_mode_set(struct ltq_spi *hw)
384 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETEN, LTQ_SPI_WHBSTATE);
389 +static u32 ltq_spi_tx_word_u8(struct ltq_spi *hw)
391 + const u8 *tx = hw->tx;
400 +static u32 ltq_spi_tx_word_u16(struct ltq_spi *hw)
402 + const u16 *tx = (u16 *) hw->tx;
411 +static u32 ltq_spi_tx_word_u32(struct ltq_spi *hw)
413 + const u32 *tx = (u32 *) hw->tx;
422 +static void ltq_spi_bits_per_word_set(struct spi_device *spi)
424 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
426 + u8 bits_per_word = spi->bits_per_word;
429 + * Use either default value of SPI device or value
430 + * from current transfer.
432 + if (hw->curr_transfer && hw->curr_transfer->bits_per_word)
433 + bits_per_word = hw->curr_transfer->bits_per_word;
435 + if (bits_per_word <= 8)
436 + hw->get_tx = ltq_spi_tx_word_u8;
437 + else if (bits_per_word <= 16)
438 + hw->get_tx = ltq_spi_tx_word_u16;
439 + else if (bits_per_word <= 32)
440 + hw->get_tx = ltq_spi_tx_word_u32;
442 + /* CON.BM value = bits_per_word - 1 */
443 + bm = (bits_per_word - 1) << LTQ_SPI_CON_BM_SHIFT;
445 + ltq_spi_reg_clearbit(hw, LTQ_SPI_CON_BM_MASK <<
446 + LTQ_SPI_CON_BM_SHIFT, LTQ_SPI_CON);
447 + ltq_spi_reg_setbit(hw, bm, LTQ_SPI_CON);
450 +static void ltq_spi_speed_set(struct spi_device *spi)
452 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
453 + u32 br, max_speed_hz, spi_clk;
454 + u32 speed_hz = spi->max_speed_hz;
457 + * Use either default value of SPI device or value
458 + * from current transfer.
460 + if (hw->curr_transfer && hw->curr_transfer->speed_hz)
461 + speed_hz = hw->curr_transfer->speed_hz;
464 + * SPI module clock is derived from FPI bus clock dependent on
465 + * divider value in CLC.RMS which is always set to 1.
467 + spi_clk = clk_get_rate(hw->fpiclk);
470 + * Maximum SPI clock frequency in master mode is half of
471 + * SPI module clock frequency. Maximum reload value of
472 + * baudrate generator BR is 2^16.
474 + max_speed_hz = spi_clk / 2;
475 + if (speed_hz >= max_speed_hz)
478 + br = (max_speed_hz / speed_hz) - 1;
483 + ltq_spi_reg_write(hw, br, LTQ_SPI_BRT);
486 +static void ltq_spi_clockmode_set(struct spi_device *spi)
488 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
491 + con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
494 + * SPI mode mapping in CON register:
495 + * Mode CPOL CPHA CON.PO CON.PH
501 + if (spi->mode & SPI_CPHA)
502 + con &= ~LTQ_SPI_CON_PH;
504 + con |= LTQ_SPI_CON_PH;
506 + if (spi->mode & SPI_CPOL)
507 + con |= LTQ_SPI_CON_PO;
509 + con &= ~LTQ_SPI_CON_PO;
511 + /* Set heading control */
512 + if (spi->mode & SPI_LSB_FIRST)
513 + con &= ~LTQ_SPI_CON_HB;
515 + con |= LTQ_SPI_CON_HB;
517 + ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
520 +static void ltq_spi_xmit_set(struct ltq_spi *hw, struct spi_transfer *t)
524 + con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
527 + if (t->tx_buf && t->rx_buf) {
528 + con &= ~(LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
529 + } else if (t->rx_buf) {
530 + con &= ~LTQ_SPI_CON_RXOFF;
531 + con |= LTQ_SPI_CON_TXOFF;
532 + } else if (t->tx_buf) {
533 + con &= ~LTQ_SPI_CON_TXOFF;
534 + con |= LTQ_SPI_CON_RXOFF;
537 + con |= (LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
539 + ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
542 +static void ltq_spi_gpio_cs_activate(struct spi_device *spi)
544 + struct ltq_spi_controller_data *cdata = spi->controller_data;
545 + int val = spi->mode & SPI_CS_HIGH ? 1 : 0;
547 + gpio_set_value(cdata->gpio, val);
550 +static void ltq_spi_gpio_cs_deactivate(struct spi_device *spi)
552 + struct ltq_spi_controller_data *cdata = spi->controller_data;
553 + int val = spi->mode & SPI_CS_HIGH ? 0 : 1;
555 + gpio_set_value(cdata->gpio, val);
558 +static void ltq_spi_internal_cs_activate(struct spi_device *spi)
560 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
563 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_CLROUTN_SHIFT));
564 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
567 +static void ltq_spi_internal_cs_deactivate(struct spi_device *spi)
569 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
572 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
573 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
576 +static void ltq_spi_chipselect(struct spi_device *spi, int cs)
578 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
579 + struct ltq_spi_controller_state *cstate = spi->controller_state;
582 + case BITBANG_CS_ACTIVE:
583 + ltq_spi_bits_per_word_set(spi);
584 + ltq_spi_speed_set(spi);
585 + ltq_spi_clockmode_set(spi);
586 + ltq_spi_run_mode_set(hw);
588 + cstate->cs_activate(spi);
591 + case BITBANG_CS_INACTIVE:
592 + cstate->cs_deactivate(spi);
594 + ltq_spi_config_mode_set(hw);
600 +static int ltq_spi_setup_transfer(struct spi_device *spi,
601 + struct spi_transfer *t)
603 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
604 + u8 bits_per_word = spi->bits_per_word;
606 + hw->curr_transfer = t;
608 + if (t && t->bits_per_word)
609 + bits_per_word = t->bits_per_word;
611 + if (bits_per_word > 32)
614 + ltq_spi_config_mode_set(hw);
619 +static const struct ltq_spi_cs_gpio_map ltq_spi_cs[] = {
628 +static int ltq_spi_setup(struct spi_device *spi)
630 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
631 + struct ltq_spi_controller_data *cdata = spi->controller_data;
632 + struct ltq_spi_controller_state *cstate;
636 + /* Set default word length to 8 if not set */
637 + if (!spi->bits_per_word)
638 + spi->bits_per_word = 8;
640 + if (spi->bits_per_word > 32)
643 + if (!spi->controller_state) {
644 + cstate = kzalloc(sizeof(struct ltq_spi_controller_state),
649 + spi->controller_state = cstate;
654 + * Up to six GPIOs can be connected to the SPI module
655 + * via GPIO alternate function to control the chip select lines.
656 + * For more flexibility in board layout this driver can also control
657 + * the CS lines via GPIO API. If GPIOs should be used, board setup code
658 + * have to register the SPI device with struct ltq_spi_controller_data
661 + if (cdata && cdata->gpio) {
662 + ret = gpio_request(cdata->gpio, "spi-cs");
666 + ret = spi->mode & SPI_CS_HIGH ? 0 : 1;
667 + gpio_direction_output(cdata->gpio, ret);
669 + cstate->cs_activate = ltq_spi_gpio_cs_activate;
670 + cstate->cs_deactivate = ltq_spi_gpio_cs_deactivate;
672 + ret = ltq_gpio_request(&spi->dev, ltq_spi_cs[spi->chip_select].gpio,
673 + ltq_spi_cs[spi->chip_select].mux,
678 + gpocon = (1 << (spi->chip_select +
679 + LTQ_SPI_GPOCON_ISCSBN_SHIFT));
681 + if (spi->mode & SPI_CS_HIGH)
682 + gpocon |= (1 << spi->chip_select);
684 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
686 + ltq_spi_reg_setbit(hw, gpocon, LTQ_SPI_GPOCON);
687 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
689 + cstate->cs_activate = ltq_spi_internal_cs_activate;
690 + cstate->cs_deactivate = ltq_spi_internal_cs_deactivate;
696 +static void ltq_spi_cleanup(struct spi_device *spi)
698 + struct ltq_spi_controller_data *cdata = spi->controller_data;
699 + struct ltq_spi_controller_state *cstate = spi->controller_state;
702 + if (cdata && cdata->gpio)
703 + gpio = cdata->gpio;
705 + gpio = ltq_spi_cs[spi->chip_select].gpio;
711 +static void ltq_spi_txfifo_write(struct ltq_spi *hw)
716 + /* Determine how much FIFOs are free for TX data */
717 + fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
718 + fifo_space = hw->txfs - ((fstat >> LTQ_SPI_FSTAT_TXFFL_SHIFT) &
719 + LTQ_SPI_FSTAT_TXFFL_MASK);
724 + while (hw->tx_cnt < hw->len && fifo_space) {
725 + data = hw->get_tx(hw);
726 + ltq_spi_reg_write(hw, data, LTQ_SPI_TB);
731 +static void ltq_spi_rxfifo_read(struct ltq_spi *hw)
733 + u32 fstat, data, *rx32;
735 + u8 rxbv, shift, *rx8;
737 + /* Determine how much FIFOs are filled with RX data */
738 + fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
739 + fifo_fill = ((fstat >> LTQ_SPI_FSTAT_RXFFL_SHIFT)
740 + & LTQ_SPI_FSTAT_RXFFL_MASK);
746 + * The 32 bit FIFO is always used completely independent from the
747 + * bits_per_word value. Thus four bytes have to be read at once
750 + rx32 = (u32 *) hw->rx;
751 + while (hw->len - hw->rx_cnt >= 4 && fifo_fill) {
752 + *rx32++ = ltq_spi_reg_read(hw, LTQ_SPI_RB);
759 + * If there are remaining bytes, read byte count from STAT.RXBV
760 + * register and read the data byte-wise.
762 + while (fifo_fill && hw->rx_cnt < hw->len) {
763 + rxbv = (ltq_spi_reg_read(hw, LTQ_SPI_STAT) >>
764 + LTQ_SPI_STAT_RXBV_SHIFT) & LTQ_SPI_STAT_RXBV_MASK;
765 + data = ltq_spi_reg_read(hw, LTQ_SPI_RB);
767 + shift = (rxbv - 1) * 8;
771 + *rx8++ = (data >> shift) & 0xFF;
782 +static void ltq_spi_rxreq_set(struct ltq_spi *hw)
784 + u32 rxreq, rxreq_max, rxtodo;
786 + rxtodo = ltq_spi_reg_read(hw, LTQ_SPI_RXCNT) & LTQ_SPI_RXCNT_TODO_MASK;
789 + * In RX-only mode the serial clock is activated only after writing
790 + * the expected amount of RX bytes into RXREQ register.
791 + * To avoid receive overflows at high clocks it is better to request
792 + * only the amount of bytes that fits into all FIFOs. This value
793 + * depends on the FIFO size implemented in hardware.
795 + rxreq = hw->len - hw->rx_cnt;
796 + rxreq_max = hw->rxfs << 2;
797 + rxreq = min(rxreq_max, rxreq);
799 + if (!rxtodo && rxreq)
800 + ltq_spi_reg_write(hw, rxreq, LTQ_SPI_RXREQ);
803 +static inline void ltq_spi_complete(struct ltq_spi *hw)
805 + complete(&hw->done);
808 +irqreturn_t ltq_spi_tx_irq(int irq, void *data)
810 + struct ltq_spi *hw = data;
811 + unsigned long flags;
814 + spin_lock_irqsave(&hw->lock, flags);
816 + if (hw->tx_cnt < hw->len)
817 + ltq_spi_txfifo_write(hw);
819 + if (hw->tx_cnt == hw->len)
822 + spin_unlock_irqrestore(&hw->lock, flags);
825 + ltq_spi_complete(hw);
827 + return IRQ_HANDLED;
830 +irqreturn_t ltq_spi_rx_irq(int irq, void *data)
832 + struct ltq_spi *hw = data;
833 + unsigned long flags;
836 + spin_lock_irqsave(&hw->lock, flags);
838 + if (hw->rx_cnt < hw->len) {
839 + ltq_spi_rxfifo_read(hw);
841 + if (hw->tx && hw->tx_cnt < hw->len)
842 + ltq_spi_txfifo_write(hw);
845 + if (hw->rx_cnt == hw->len)
848 + ltq_spi_rxreq_set(hw);
850 + spin_unlock_irqrestore(&hw->lock, flags);
853 + ltq_spi_complete(hw);
855 + return IRQ_HANDLED;
858 +irqreturn_t ltq_spi_err_irq(int irq, void *data)
860 + struct ltq_spi *hw = data;
861 + unsigned long flags;
863 + spin_lock_irqsave(&hw->lock, flags);
865 + /* Disable all interrupts */
866 + ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
868 + /* Clear all error flags */
869 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
872 + ltq_spi_reg_setbit(hw, LTQ_SPI_RXFCON_RXFLU, LTQ_SPI_RXFCON);
873 + ltq_spi_reg_setbit(hw, LTQ_SPI_TXFCON_TXFLU, LTQ_SPI_TXFCON);
876 + spin_unlock_irqrestore(&hw->lock, flags);
878 + ltq_spi_complete(hw);
880 + return IRQ_HANDLED;
883 +static int ltq_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
885 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
888 + hw->tx = t->tx_buf;
889 + hw->rx = t->rx_buf;
894 + INIT_COMPLETION(hw->done);
896 + ltq_spi_xmit_set(hw, t);
898 + /* Enable error interrupts */
899 + ltq_spi_reg_setbit(hw, LTQ_SPI_IRNEN_E, LTQ_SPI_IRNEN);
902 + /* Initially fill TX FIFO with as much data as possible */
903 + ltq_spi_txfifo_write(hw);
904 + irq_flags |= LTQ_SPI_IRNEN_T;
906 + /* Always enable RX interrupt in Full Duplex mode */
908 + irq_flags |= LTQ_SPI_IRNEN_R;
909 + } else if (hw->rx) {
910 + /* Start RX clock */
911 + ltq_spi_rxreq_set(hw);
913 + /* Enable RX interrupt to receive data from RX FIFOs */
914 + irq_flags |= LTQ_SPI_IRNEN_R;
917 + /* Enable TX or RX interrupts */
918 + ltq_spi_reg_setbit(hw, irq_flags, LTQ_SPI_IRNEN);
919 + wait_for_completion_interruptible(&hw->done);
921 + /* Disable all interrupts */
922 + ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
925 + * Return length of current transfer for bitbang utility code if
926 + * no errors occured during transmission.
929 + hw->status = hw->len;
934 +static const struct ltq_spi_irq_map ltq_spi_irqs[] = {
935 + { "spi_tx", ltq_spi_tx_irq },
936 + { "spi_rx", ltq_spi_rx_irq },
937 + { "spi_err", ltq_spi_err_irq },
940 +static int __init ltq_spi_probe(struct platform_device *pdev)
942 + struct spi_master *master;
943 + struct resource *r;
944 + struct ltq_spi *hw;
945 + struct ltq_spi_platform_data *pdata = pdev->dev.platform_data;
949 + master = spi_alloc_master(&pdev->dev, sizeof(struct ltq_spi));
951 + dev_err(&pdev->dev, "spi_alloc_master\n");
956 + hw = spi_master_get_devdata(master);
958 + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
960 + dev_err(&pdev->dev, "platform_get_resource\n");
965 + r = devm_request_mem_region(&pdev->dev, r->start, resource_size(r),
968 + dev_err(&pdev->dev, "devm_request_mem_region\n");
973 + hw->base = devm_ioremap_nocache(&pdev->dev, r->start, resource_size(r));
975 + dev_err(&pdev->dev, "devm_ioremap_nocache\n");
980 + hw->fpiclk = clk_get_fpi();
981 + if (IS_ERR(hw->fpiclk)) {
982 + dev_err(&pdev->dev, "clk_get\n");
983 + ret = PTR_ERR(hw->fpiclk);
987 + hw->spiclk = clk_get(&pdev->dev, NULL);
988 + if (IS_ERR(hw->spiclk)) {
989 + dev_err(&pdev->dev, "clk_get\n");
990 + ret = PTR_ERR(hw->spiclk);
994 + memset(hw->irq, 0, sizeof(hw->irq));
995 + for (i = 0; i < ARRAY_SIZE(ltq_spi_irqs); i++) {
996 + ret = platform_get_irq_byname(pdev, ltq_spi_irqs[i].name);
998 + dev_err(&pdev->dev, "platform_get_irq_byname\n");
1003 + ret = request_irq(hw->irq[i], ltq_spi_irqs[i].handler,
1004 + 0, ltq_spi_irqs[i].name, hw);
1006 + dev_err(&pdev->dev, "request_irq\n");
1011 + hw->bitbang.master = spi_master_get(master);
1012 + hw->bitbang.chipselect = ltq_spi_chipselect;
1013 + hw->bitbang.setup_transfer = ltq_spi_setup_transfer;
1014 + hw->bitbang.txrx_bufs = ltq_spi_txrx_bufs;
1016 + master->bus_num = pdev->id;
1017 + master->num_chipselect = pdata->num_chipselect;
1018 + master->setup = ltq_spi_setup;
1019 + master->cleanup = ltq_spi_cleanup;
1021 + hw->dev = &pdev->dev;
1022 + init_completion(&hw->done);
1023 + spin_lock_init(&hw->lock);
1025 + /* Set GPIO alternate functions to SPI */
1026 + ltq_gpio_request(&pdev->dev, LTQ_SPI_GPIO_DI, 2, 0, "spi-di");
1027 + ltq_gpio_request(&pdev->dev, LTQ_SPI_GPIO_DO, 2, 1, "spi-do");
1028 + ltq_gpio_request(&pdev->dev, LTQ_SPI_GPIO_CLK, 2, 1, "spi-clk");
1030 + ltq_spi_hw_enable(hw);
1032 + /* Read module capabilities */
1033 + id = ltq_spi_reg_read(hw, LTQ_SPI_ID);
1034 + hw->txfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
1035 + hw->rxfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
1036 + hw->dma_support = (id & LTQ_SPI_ID_CFG) ? 1 : 0;
1038 + ltq_spi_config_mode_set(hw);
1040 + /* Enable error checking, disable TX/RX, set idle value high */
1041 + data = LTQ_SPI_CON_RUEN | LTQ_SPI_CON_AEN |
1042 + LTQ_SPI_CON_TEN | LTQ_SPI_CON_REN |
1043 + LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF | LTQ_SPI_CON_IDLE;
1044 + ltq_spi_reg_write(hw, data, LTQ_SPI_CON);
1046 + /* Enable master mode and clear error flags */
1047 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETMS |
1048 + LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
1050 + /* Reset GPIO/CS registers */
1051 + ltq_spi_reg_write(hw, 0x0, LTQ_SPI_GPOCON);
1052 + ltq_spi_reg_write(hw, 0xFF00, LTQ_SPI_FGPO);
1054 + /* Enable and flush FIFOs */
1055 + ltq_spi_reset_fifos(hw);
1057 + ret = spi_bitbang_start(&hw->bitbang);
1059 + dev_err(&pdev->dev, "spi_bitbang_start\n");
1063 + platform_set_drvdata(pdev, hw);
1065 + pr_info("Lantiq SoC SPI controller rev %u (TXFS %u, RXFS %u, DMA %u)\n",
1066 + id & LTQ_SPI_ID_REV_MASK, hw->txfs, hw->rxfs, hw->dma_support);
1071 + ltq_spi_hw_disable(hw);
1074 + clk_put(hw->fpiclk);
1076 + for (; i > 0; i--)
1077 + free_irq(hw->irq[i], hw);
1080 + spi_master_put(master);
1086 +static int __exit ltq_spi_remove(struct platform_device *pdev)
1088 + struct ltq_spi *hw = platform_get_drvdata(pdev);
1091 + ret = spi_bitbang_stop(&hw->bitbang);
1095 + platform_set_drvdata(pdev, NULL);
1097 + ltq_spi_config_mode_set(hw);
1098 + ltq_spi_hw_disable(hw);
1100 + for (i = 0; i < ARRAY_SIZE(hw->irq); i++)
1101 + if (0 < hw->irq[i])
1102 + free_irq(hw->irq[i], hw);
1104 + gpio_free(LTQ_SPI_GPIO_DI);
1105 + gpio_free(LTQ_SPI_GPIO_DO);
1106 + gpio_free(LTQ_SPI_GPIO_CLK);
1108 + clk_put(hw->fpiclk);
1109 + spi_master_put(hw->bitbang.master);
1114 +static struct platform_driver ltq_spi_driver = {
1116 + .name = "ltq_spi",
1117 + .owner = THIS_MODULE,
1119 + .remove = __exit_p(ltq_spi_remove),
1122 +static int __init ltq_spi_init(void)
1124 + return platform_driver_probe(<q_spi_driver, ltq_spi_probe);
1126 +module_init(ltq_spi_init);
1128 +static void __exit ltq_spi_exit(void)
1130 + platform_driver_unregister(<q_spi_driver);
1132 +module_exit(ltq_spi_exit);
1134 +MODULE_DESCRIPTION("Lantiq SoC SPI controller driver");
1135 +MODULE_AUTHOR("Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>");
1136 +MODULE_LICENSE("GPL");
1137 +MODULE_ALIAS("platform:ltq-spi");