1 From e29263339db41d49d79482c93463c4c0cbe764d7 Mon Sep 17 00:00:00 2001
2 From: John Crispin <blogic@openwrt.org>
3 Date: Fri, 30 Sep 2011 14:23:42 +0200
4 Subject: [PATCH 14/24] MIPS: lantiq: adds xway spi
7 .../mips/include/asm/mach-lantiq/lantiq_platform.h | 9 +
8 .../mips/include/asm/mach-lantiq/xway/lantiq_irq.h | 2 +
9 .../mips/include/asm/mach-lantiq/xway/lantiq_soc.h | 1 +
10 drivers/spi/Kconfig | 8 +
11 drivers/spi/Makefile | 2 +-
12 drivers/spi/spi-xway.c | 1062 ++++++++++++++++++++
13 6 files changed, 1083 insertions(+), 1 deletions(-)
14 create mode 100644 drivers/spi/spi-xway.c
16 --- a/arch/mips/include/asm/mach-lantiq/lantiq_platform.h
17 +++ b/arch/mips/include/asm/mach-lantiq/lantiq_platform.h
18 @@ -50,4 +50,13 @@ struct ltq_eth_data {
23 +struct ltq_spi_platform_data {
27 +struct ltq_spi_controller_data {
32 --- a/arch/mips/include/asm/mach-lantiq/xway/lantiq_irq.h
33 +++ b/arch/mips/include/asm/mach-lantiq/xway/lantiq_irq.h
36 #define LTQ_SSC_TIR (INT_NUM_IM0_IRL0 + 15)
37 #define LTQ_SSC_RIR (INT_NUM_IM0_IRL0 + 14)
38 +#define LTQ_SSC_TIR_AR9 (INT_NUM_IM0_IRL0 + 14)
39 +#define LTQ_SSC_RIR_AR9 (INT_NUM_IM0_IRL0 + 15)
40 #define LTQ_SSC_EIR (INT_NUM_IM0_IRL0 + 16)
42 #define LTQ_MEI_DYING_GASP_INT (INT_NUM_IM1_IRL0 + 21)
43 --- a/arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h
44 +++ b/arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h
47 #define PMU_DMA 0x0020
48 #define PMU_USB 0x8041
49 +#define PMU_SPI 0x0100
50 #define PMU_LED 0x0800
51 #define PMU_GPT 0x1000
52 #define PMU_PPE 0x2000
53 --- a/drivers/spi/Kconfig
54 +++ b/drivers/spi/Kconfig
55 @@ -393,6 +393,14 @@ config SPI_NUC900
57 SPI driver for Nuvoton NUC900 series ARM SoCs
60 + tristate "Lantiq XWAY SPI controller"
61 + depends on LANTIQ && SOC_TYPE_XWAY
64 + This driver supports the Lantiq SoC SPI controller in master
68 # Add new SPI master controllers in alphabetical order above this line
70 --- a/drivers/spi/Makefile
71 +++ b/drivers/spi/Makefile
72 @@ -60,4 +60,5 @@ obj-$(CONFIG_SPI_TLE62X0) += spi-tle62x
73 obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o
74 obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
75 obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
76 +obj-$(CONFIG_SPI_XWAY) += spi-xway.o
79 +++ b/drivers/spi/spi-xway.c
82 + * Lantiq SoC SPI controller
84 + * Copyright (C) 2011 Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
86 + * This program is free software; you can distribute it and/or modify it
87 + * under the terms of the GNU General Public License (Version 2) as
88 + * published by the Free Software Foundation.
91 +#include <linux/init.h>
92 +#include <linux/module.h>
93 +#include <linux/workqueue.h>
94 +#include <linux/platform_device.h>
95 +#include <linux/io.h>
96 +#include <linux/sched.h>
97 +#include <linux/delay.h>
98 +#include <linux/interrupt.h>
99 +#include <linux/completion.h>
100 +#include <linux/spinlock.h>
101 +#include <linux/err.h>
102 +#include <linux/clk.h>
103 +#include <linux/gpio.h>
104 +#include <linux/spi/spi.h>
105 +#include <linux/spi/spi_bitbang.h>
107 +#include <lantiq_soc.h>
108 +#include <lantiq_platform.h>
110 +#define LTQ_SPI_CLC 0x00 /* Clock control */
111 +#define LTQ_SPI_PISEL 0x04 /* Port input select */
112 +#define LTQ_SPI_ID 0x08 /* Identification */
113 +#define LTQ_SPI_CON 0x10 /* Control */
114 +#define LTQ_SPI_STAT 0x14 /* Status */
115 +#define LTQ_SPI_WHBSTATE 0x18 /* Write HW modified state */
116 +#define LTQ_SPI_TB 0x20 /* Transmit buffer */
117 +#define LTQ_SPI_RB 0x24 /* Receive buffer */
118 +#define LTQ_SPI_RXFCON 0x30 /* Receive FIFO control */
119 +#define LTQ_SPI_TXFCON 0x34 /* Transmit FIFO control */
120 +#define LTQ_SPI_FSTAT 0x38 /* FIFO status */
121 +#define LTQ_SPI_BRT 0x40 /* Baudrate timer */
122 +#define LTQ_SPI_BRSTAT 0x44 /* Baudrate timer status */
123 +#define LTQ_SPI_SFCON 0x60 /* Serial frame control */
124 +#define LTQ_SPI_SFSTAT 0x64 /* Serial frame status */
125 +#define LTQ_SPI_GPOCON 0x70 /* General purpose output control */
126 +#define LTQ_SPI_GPOSTAT 0x74 /* General purpose output status */
127 +#define LTQ_SPI_FGPO 0x78 /* Forced general purpose output */
128 +#define LTQ_SPI_RXREQ 0x80 /* Receive request */
129 +#define LTQ_SPI_RXCNT 0x84 /* Receive count */
130 +#define LTQ_SPI_DMACON 0xEC /* DMA control */
131 +#define LTQ_SPI_IRNEN 0xF4 /* Interrupt node enable */
132 +#define LTQ_SPI_IRNICR 0xF8 /* Interrupt node interrupt capture */
133 +#define LTQ_SPI_IRNCR 0xFC /* Interrupt node control */
135 +#define LTQ_SPI_CLC_SMC_SHIFT 16 /* Clock divider for sleep mode */
136 +#define LTQ_SPI_CLC_SMC_MASK 0xFF
137 +#define LTQ_SPI_CLC_RMC_SHIFT 8 /* Clock divider for normal run mode */
138 +#define LTQ_SPI_CLC_RMC_MASK 0xFF
139 +#define LTQ_SPI_CLC_DISS BIT(1) /* Disable status bit */
140 +#define LTQ_SPI_CLC_DISR BIT(0) /* Disable request bit */
142 +#define LTQ_SPI_ID_TXFS_SHIFT 24 /* Implemented TX FIFO size */
143 +#define LTQ_SPI_ID_TXFS_MASK 0x3F
144 +#define LTQ_SPI_ID_RXFS_SHIFT 16 /* Implemented RX FIFO size */
145 +#define LTQ_SPI_ID_RXFS_MASK 0x3F
146 +#define LTQ_SPI_ID_REV_MASK 0x1F /* Hardware revision number */
147 +#define LTQ_SPI_ID_CFG BIT(5) /* DMA interface support */
149 +#define LTQ_SPI_CON_BM_SHIFT 16 /* Data width selection */
150 +#define LTQ_SPI_CON_BM_MASK 0x1F
151 +#define LTQ_SPI_CON_EM BIT(24) /* Echo mode */
152 +#define LTQ_SPI_CON_IDLE BIT(23) /* Idle bit value */
153 +#define LTQ_SPI_CON_ENBV BIT(22) /* Enable byte valid control */
154 +#define LTQ_SPI_CON_RUEN BIT(12) /* Receive underflow error enable */
155 +#define LTQ_SPI_CON_TUEN BIT(11) /* Transmit underflow error enable */
156 +#define LTQ_SPI_CON_AEN BIT(10) /* Abort error enable */
157 +#define LTQ_SPI_CON_REN BIT(9) /* Receive overflow error enable */
158 +#define LTQ_SPI_CON_TEN BIT(8) /* Transmit overflow error enable */
159 +#define LTQ_SPI_CON_LB BIT(7) /* Loopback control */
160 +#define LTQ_SPI_CON_PO BIT(6) /* Clock polarity control */
161 +#define LTQ_SPI_CON_PH BIT(5) /* Clock phase control */
162 +#define LTQ_SPI_CON_HB BIT(4) /* Heading control */
163 +#define LTQ_SPI_CON_RXOFF BIT(1) /* Switch receiver off */
164 +#define LTQ_SPI_CON_TXOFF BIT(0) /* Switch transmitter off */
166 +#define LTQ_SPI_STAT_RXBV_MASK 0x7
167 +#define LTQ_SPI_STAT_RXBV_SHIFT 28
168 +#define LTQ_SPI_STAT_BSY BIT(13) /* Busy flag */
169 +#define LTQ_SPI_STAT_RUE BIT(12) /* Receive underflow error flag */
170 +#define LTQ_SPI_STAT_TUE BIT(11) /* Transmit underflow error flag */
171 +#define LTQ_SPI_STAT_AE BIT(10) /* Abort error flag */
172 +#define LTQ_SPI_STAT_RE BIT(9) /* Receive error flag */
173 +#define LTQ_SPI_STAT_TE BIT(8) /* Transmit error flag */
174 +#define LTQ_SPI_STAT_MS BIT(1) /* Master/slave select bit */
175 +#define LTQ_SPI_STAT_EN BIT(0) /* Enable bit */
177 +#define LTQ_SPI_WHBSTATE_SETTUE BIT(15) /* Set transmit underflow error flag */
178 +#define LTQ_SPI_WHBSTATE_SETAE BIT(14) /* Set abort error flag */
179 +#define LTQ_SPI_WHBSTATE_SETRE BIT(13) /* Set receive error flag */
180 +#define LTQ_SPI_WHBSTATE_SETTE BIT(12) /* Set transmit error flag */
181 +#define LTQ_SPI_WHBSTATE_CLRTUE BIT(11) /* Clear transmit underflow error flag */
182 +#define LTQ_SPI_WHBSTATE_CLRAE BIT(10) /* Clear abort error flag */
183 +#define LTQ_SPI_WHBSTATE_CLRRE BIT(9) /* Clear receive error flag */
184 +#define LTQ_SPI_WHBSTATE_CLRTE BIT(8) /* Clear transmit error flag */
185 +#define LTQ_SPI_WHBSTATE_SETME BIT(7) /* Set mode error flag */
186 +#define LTQ_SPI_WHBSTATE_CLRME BIT(6) /* Clear mode error flag */
187 +#define LTQ_SPI_WHBSTATE_SETRUE BIT(5) /* Set receive underflow error flag */
188 +#define LTQ_SPI_WHBSTATE_CLRRUE BIT(4) /* Clear receive underflow error flag */
189 +#define LTQ_SPI_WHBSTATE_SETMS BIT(3) /* Set master select bit */
190 +#define LTQ_SPI_WHBSTATE_CLRMS BIT(2) /* Clear master select bit */
191 +#define LTQ_SPI_WHBSTATE_SETEN BIT(1) /* Set enable bit (operational mode) */
192 +#define LTQ_SPI_WHBSTATE_CLREN BIT(0) /* Clear enable bit (config mode */
193 +#define LTQ_SPI_WHBSTATE_CLR_ERRORS 0x0F50
195 +#define LTQ_SPI_RXFCON_RXFITL_SHIFT 8 /* FIFO interrupt trigger level */
196 +#define LTQ_SPI_RXFCON_RXFITL_MASK 0x3F
197 +#define LTQ_SPI_RXFCON_RXFLU BIT(1) /* FIFO flush */
198 +#define LTQ_SPI_RXFCON_RXFEN BIT(0) /* FIFO enable */
200 +#define LTQ_SPI_TXFCON_TXFITL_SHIFT 8 /* FIFO interrupt trigger level */
201 +#define LTQ_SPI_TXFCON_TXFITL_MASK 0x3F
202 +#define LTQ_SPI_TXFCON_TXFLU BIT(1) /* FIFO flush */
203 +#define LTQ_SPI_TXFCON_TXFEN BIT(0) /* FIFO enable */
205 +#define LTQ_SPI_FSTAT_RXFFL_MASK 0x3f
206 +#define LTQ_SPI_FSTAT_RXFFL_SHIFT 0
207 +#define LTQ_SPI_FSTAT_TXFFL_MASK 0x3f
208 +#define LTQ_SPI_FSTAT_TXFFL_SHIFT 8
210 +#define LTQ_SPI_GPOCON_ISCSBN_SHIFT 8
211 +#define LTQ_SPI_GPOCON_INVOUTN_SHIFT 0
213 +#define LTQ_SPI_FGPO_SETOUTN_SHIFT 8
214 +#define LTQ_SPI_FGPO_CLROUTN_SHIFT 0
216 +#define LTQ_SPI_RXREQ_RXCNT_MASK 0xFFFF /* Receive count value */
217 +#define LTQ_SPI_RXCNT_TODO_MASK 0xFFFF /* Recevie to-do value */
219 +#define LTQ_SPI_IRNEN_F BIT(3) /* Frame end interrupt request */
220 +#define LTQ_SPI_IRNEN_E BIT(2) /* Error end interrupt request */
221 +#define LTQ_SPI_IRNEN_T BIT(1) /* Transmit end interrupt request */
222 +#define LTQ_SPI_IRNEN_R BIT(0) /* Receive end interrupt request */
223 +#define LTQ_SPI_IRNEN_ALL 0xF
225 +/* Hard-wired GPIOs used by SPI controller */
226 +#define LTQ_SPI_GPIO_DI 16
227 +#define LTQ_SPI_GPIO_DO 17
228 +#define LTQ_SPI_GPIO_CLK 18
231 + struct spi_bitbang bitbang;
232 + struct completion done;
235 + struct device *dev;
236 + void __iomem *base;
247 + struct spi_transfer *curr_transfer;
249 + u32 (*get_tx) (struct ltq_spi *);
253 + unsigned dma_support:1;
254 + unsigned cfg_mode:1;
258 +struct ltq_spi_controller_state {
259 + void (*cs_activate) (struct spi_device *);
260 + void (*cs_deactivate) (struct spi_device *);
263 +struct ltq_spi_irq_map {
265 + irq_handler_t handler;
268 +struct ltq_spi_cs_gpio_map {
274 +static inline struct ltq_spi *ltq_spi_to_hw(struct spi_device *spi)
276 + return spi_master_get_devdata(spi->master);
279 +static inline u32 ltq_spi_reg_read(struct ltq_spi *hw, u32 reg)
281 + return ioread32be(hw->base + reg);
284 +static inline void ltq_spi_reg_write(struct ltq_spi *hw, u32 val, u32 reg)
286 + iowrite32be(val, hw->base + reg);
289 +static inline void ltq_spi_reg_setbit(struct ltq_spi *hw, u32 bits, u32 reg)
293 + val = ltq_spi_reg_read(hw, reg);
295 + ltq_spi_reg_write(hw, val, reg);
298 +static inline void ltq_spi_reg_clearbit(struct ltq_spi *hw, u32 bits, u32 reg)
302 + val = ltq_spi_reg_read(hw, reg);
304 + ltq_spi_reg_write(hw, val, reg);
307 +static void ltq_spi_hw_enable(struct ltq_spi *hw)
311 + /* Power-up mdule */
312 + ltq_pmu_enable(PMU_SPI);
315 + * Set clock divider for run mode to 1 to
316 + * run at same frequency as FPI bus
318 + clc = (1 << LTQ_SPI_CLC_RMC_SHIFT);
319 + ltq_spi_reg_write(hw, clc, LTQ_SPI_CLC);
322 +static void ltq_spi_hw_disable(struct ltq_spi *hw)
324 + /* Set clock divider to 0 and set module disable bit */
325 + ltq_spi_reg_write(hw, LTQ_SPI_CLC_DISS, LTQ_SPI_CLC);
327 + /* Power-down mdule */
328 + ltq_pmu_disable(PMU_SPI);
331 +static void ltq_spi_reset_fifos(struct ltq_spi *hw)
336 + * Enable and flush FIFOs. Set interrupt trigger level to
337 + * half of FIFO count implemented in hardware.
339 + if (hw->txfs > 1) {
340 + val = hw->txfs << (LTQ_SPI_TXFCON_TXFITL_SHIFT - 1);
341 + val |= LTQ_SPI_TXFCON_TXFEN | LTQ_SPI_TXFCON_TXFLU;
342 + ltq_spi_reg_write(hw, val, LTQ_SPI_TXFCON);
345 + if (hw->rxfs > 1) {
346 + val = hw->rxfs << (LTQ_SPI_RXFCON_RXFITL_SHIFT - 1);
347 + val |= LTQ_SPI_RXFCON_RXFEN | LTQ_SPI_RXFCON_RXFLU;
348 + ltq_spi_reg_write(hw, val, LTQ_SPI_RXFCON);
352 +static inline int ltq_spi_wait_ready(struct ltq_spi *hw)
355 + unsigned long timeout;
357 + timeout = jiffies + msecs_to_jiffies(200);
360 + stat = ltq_spi_reg_read(hw, LTQ_SPI_STAT);
361 + if (!(stat & LTQ_SPI_STAT_BSY))
365 + } while (!time_after_eq(jiffies, timeout));
367 + dev_err(hw->dev, "SPI wait ready timed out\n");
372 +static void ltq_spi_config_mode_set(struct ltq_spi *hw)
378 + * Putting the SPI module in config mode is only safe if no
379 + * transfer is in progress as indicated by busy flag STATE.BSY.
381 + if (ltq_spi_wait_ready(hw)) {
382 + ltq_spi_reset_fifos(hw);
383 + hw->status = -ETIMEDOUT;
385 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLREN, LTQ_SPI_WHBSTATE);
390 +static void ltq_spi_run_mode_set(struct ltq_spi *hw)
395 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETEN, LTQ_SPI_WHBSTATE);
400 +static u32 ltq_spi_tx_word_u8(struct ltq_spi *hw)
402 + const u8 *tx = hw->tx;
411 +static u32 ltq_spi_tx_word_u16(struct ltq_spi *hw)
413 + const u16 *tx = (u16 *) hw->tx;
422 +static u32 ltq_spi_tx_word_u32(struct ltq_spi *hw)
424 + const u32 *tx = (u32 *) hw->tx;
433 +static void ltq_spi_bits_per_word_set(struct spi_device *spi)
435 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
437 + u8 bits_per_word = spi->bits_per_word;
440 + * Use either default value of SPI device or value
441 + * from current transfer.
443 + if (hw->curr_transfer && hw->curr_transfer->bits_per_word)
444 + bits_per_word = hw->curr_transfer->bits_per_word;
446 + if (bits_per_word <= 8)
447 + hw->get_tx = ltq_spi_tx_word_u8;
448 + else if (bits_per_word <= 16)
449 + hw->get_tx = ltq_spi_tx_word_u16;
450 + else if (bits_per_word <= 32)
451 + hw->get_tx = ltq_spi_tx_word_u32;
453 + /* CON.BM value = bits_per_word - 1 */
454 + bm = (bits_per_word - 1) << LTQ_SPI_CON_BM_SHIFT;
456 + ltq_spi_reg_clearbit(hw, LTQ_SPI_CON_BM_MASK <<
457 + LTQ_SPI_CON_BM_SHIFT, LTQ_SPI_CON);
458 + ltq_spi_reg_setbit(hw, bm, LTQ_SPI_CON);
461 +static void ltq_spi_speed_set(struct spi_device *spi)
463 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
464 + u32 br, max_speed_hz, spi_clk;
465 + u32 speed_hz = spi->max_speed_hz;
468 + * Use either default value of SPI device or value
469 + * from current transfer.
471 + if (hw->curr_transfer && hw->curr_transfer->speed_hz)
472 + speed_hz = hw->curr_transfer->speed_hz;
475 + * SPI module clock is derived from FPI bus clock dependent on
476 + * divider value in CLC.RMS which is always set to 1.
478 + spi_clk = clk_get_rate(hw->clk);
481 + * Maximum SPI clock frequency in master mode is half of
482 + * SPI module clock frequency. Maximum reload value of
483 + * baudrate generator BR is 2^16.
485 + max_speed_hz = spi_clk / 2;
486 + if (speed_hz >= max_speed_hz)
489 + br = (max_speed_hz / speed_hz) - 1;
494 + ltq_spi_reg_write(hw, br, LTQ_SPI_BRT);
497 +static void ltq_spi_clockmode_set(struct spi_device *spi)
499 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
502 + con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
505 + * SPI mode mapping in CON register:
506 + * Mode CPOL CPHA CON.PO CON.PH
512 + if (spi->mode & SPI_CPHA)
513 + con &= ~LTQ_SPI_CON_PH;
515 + con |= LTQ_SPI_CON_PH;
517 + if (spi->mode & SPI_CPOL)
518 + con |= LTQ_SPI_CON_PO;
520 + con &= ~LTQ_SPI_CON_PO;
522 + /* Set heading control */
523 + if (spi->mode & SPI_LSB_FIRST)
524 + con &= ~LTQ_SPI_CON_HB;
526 + con |= LTQ_SPI_CON_HB;
528 + ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
531 +static void ltq_spi_xmit_set(struct ltq_spi *hw, struct spi_transfer *t)
535 + con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
538 + if (t->tx_buf && t->rx_buf) {
539 + con &= ~(LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
540 + } else if (t->rx_buf) {
541 + con &= ~LTQ_SPI_CON_RXOFF;
542 + con |= LTQ_SPI_CON_TXOFF;
543 + } else if (t->tx_buf) {
544 + con &= ~LTQ_SPI_CON_TXOFF;
545 + con |= LTQ_SPI_CON_RXOFF;
548 + con |= (LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
550 + ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
553 +static void ltq_spi_gpio_cs_activate(struct spi_device *spi)
555 + struct ltq_spi_controller_data *cdata = spi->controller_data;
556 + int val = spi->mode & SPI_CS_HIGH ? 1 : 0;
558 + gpio_set_value(cdata->gpio, val);
561 +static void ltq_spi_gpio_cs_deactivate(struct spi_device *spi)
563 + struct ltq_spi_controller_data *cdata = spi->controller_data;
564 + int val = spi->mode & SPI_CS_HIGH ? 0 : 1;
566 + gpio_set_value(cdata->gpio, val);
569 +static void ltq_spi_internal_cs_activate(struct spi_device *spi)
571 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
574 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_CLROUTN_SHIFT));
575 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
578 +static void ltq_spi_internal_cs_deactivate(struct spi_device *spi)
580 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
583 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
584 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
587 +static void ltq_spi_chipselect(struct spi_device *spi, int cs)
589 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
590 + struct ltq_spi_controller_state *cstate = spi->controller_state;
593 + case BITBANG_CS_ACTIVE:
594 + ltq_spi_bits_per_word_set(spi);
595 + ltq_spi_speed_set(spi);
596 + ltq_spi_clockmode_set(spi);
597 + ltq_spi_run_mode_set(hw);
599 + cstate->cs_activate(spi);
602 + case BITBANG_CS_INACTIVE:
603 + cstate->cs_deactivate(spi);
605 + ltq_spi_config_mode_set(hw);
611 +static int ltq_spi_setup_transfer(struct spi_device *spi,
612 + struct spi_transfer *t)
614 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
615 + u8 bits_per_word = spi->bits_per_word;
617 + hw->curr_transfer = t;
619 + if (t && t->bits_per_word)
620 + bits_per_word = t->bits_per_word;
622 + if (bits_per_word > 32)
625 + ltq_spi_config_mode_set(hw);
630 +static const struct ltq_spi_cs_gpio_map ltq_spi_cs[] = {
639 +static int ltq_spi_setup(struct spi_device *spi)
641 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
642 + struct ltq_spi_controller_data *cdata = spi->controller_data;
643 + struct ltq_spi_controller_state *cstate;
647 + /* Set default word length to 8 if not set */
648 + if (!spi->bits_per_word)
649 + spi->bits_per_word = 8;
651 + if (spi->bits_per_word > 32)
654 + if (!spi->controller_state) {
655 + cstate = kzalloc(sizeof(struct ltq_spi_controller_state),
660 + spi->controller_state = cstate;
665 + * Up to six GPIOs can be connected to the SPI module
666 + * via GPIO alternate function to control the chip select lines.
667 + * For more flexibility in board layout this driver can also control
668 + * the CS lines via GPIO API. If GPIOs should be used, board setup code
669 + * have to register the SPI device with struct ltq_spi_controller_data
672 + if (cdata && cdata->gpio) {
673 + ret = gpio_request(cdata->gpio, "spi-cs");
677 + ret = spi->mode & SPI_CS_HIGH ? 0 : 1;
678 + gpio_direction_output(cdata->gpio, ret);
680 + cstate->cs_activate = ltq_spi_gpio_cs_activate;
681 + cstate->cs_deactivate = ltq_spi_gpio_cs_deactivate;
683 + ret = ltq_gpio_request(ltq_spi_cs[spi->chip_select].gpio,
684 + ltq_spi_cs[spi->chip_select].altsel0,
685 + ltq_spi_cs[spi->chip_select].altsel1,
690 + gpocon = (1 << (spi->chip_select +
691 + LTQ_SPI_GPOCON_ISCSBN_SHIFT));
693 + if (spi->mode & SPI_CS_HIGH)
694 + gpocon |= (1 << spi->chip_select);
696 + fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
698 + ltq_spi_reg_setbit(hw, gpocon, LTQ_SPI_GPOCON);
699 + ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
701 + cstate->cs_activate = ltq_spi_internal_cs_activate;
702 + cstate->cs_deactivate = ltq_spi_internal_cs_deactivate;
708 +static void ltq_spi_cleanup(struct spi_device *spi)
710 + struct ltq_spi_controller_data *cdata = spi->controller_data;
711 + struct ltq_spi_controller_state *cstate = spi->controller_state;
714 + if (cdata && cdata->gpio)
715 + gpio = cdata->gpio;
717 + gpio = ltq_spi_cs[spi->chip_select].gpio;
723 +static void ltq_spi_txfifo_write(struct ltq_spi *hw)
728 + /* Determine how much FIFOs are free for TX data */
729 + fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
730 + fifo_space = hw->txfs - ((fstat >> LTQ_SPI_FSTAT_TXFFL_SHIFT) &
731 + LTQ_SPI_FSTAT_TXFFL_MASK);
736 + while (hw->tx_cnt < hw->len && fifo_space) {
737 + data = hw->get_tx(hw);
738 + ltq_spi_reg_write(hw, data, LTQ_SPI_TB);
743 +static void ltq_spi_rxfifo_read(struct ltq_spi *hw)
745 + u32 fstat, data, *rx32;
747 + u8 rxbv, shift, *rx8;
749 + /* Determine how much FIFOs are filled with RX data */
750 + fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
751 + fifo_fill = ((fstat >> LTQ_SPI_FSTAT_RXFFL_SHIFT)
752 + & LTQ_SPI_FSTAT_RXFFL_MASK);
758 + * The 32 bit FIFO is always used completely independent from the
759 + * bits_per_word value. Thus four bytes have to be read at once
762 + rx32 = (u32 *) hw->rx;
763 + while (hw->len - hw->rx_cnt >= 4 && fifo_fill) {
764 + *rx32++ = ltq_spi_reg_read(hw, LTQ_SPI_RB);
771 + * If there are remaining bytes, read byte count from STAT.RXBV
772 + * register and read the data byte-wise.
774 + while (fifo_fill && hw->rx_cnt < hw->len) {
775 + rxbv = (ltq_spi_reg_read(hw, LTQ_SPI_STAT) >>
776 + LTQ_SPI_STAT_RXBV_SHIFT) & LTQ_SPI_STAT_RXBV_MASK;
777 + data = ltq_spi_reg_read(hw, LTQ_SPI_RB);
779 + shift = (rxbv - 1) * 8;
783 + *rx8++ = (data >> shift) & 0xFF;
794 +static void ltq_spi_rxreq_set(struct ltq_spi *hw)
796 + u32 rxreq, rxreq_max, rxtodo;
798 + rxtodo = ltq_spi_reg_read(hw, LTQ_SPI_RXCNT) & LTQ_SPI_RXCNT_TODO_MASK;
801 + * In RX-only mode the serial clock is activated only after writing
802 + * the expected amount of RX bytes into RXREQ register.
803 + * To avoid receive overflows at high clocks it is better to request
804 + * only the amount of bytes that fits into all FIFOs. This value
805 + * depends on the FIFO size implemented in hardware.
807 + rxreq = hw->len - hw->rx_cnt;
808 + rxreq_max = hw->rxfs << 2;
809 + rxreq = min(rxreq_max, rxreq);
811 + if (!rxtodo && rxreq)
812 + ltq_spi_reg_write(hw, rxreq, LTQ_SPI_RXREQ);
815 +static inline void ltq_spi_complete(struct ltq_spi *hw)
817 + complete(&hw->done);
820 +irqreturn_t ltq_spi_tx_irq(int irq, void *data)
822 + struct ltq_spi *hw = data;
823 + unsigned long flags;
826 + spin_lock_irqsave(&hw->lock, flags);
828 + if (hw->tx_cnt < hw->len)
829 + ltq_spi_txfifo_write(hw);
831 + if (hw->tx_cnt == hw->len)
834 + spin_unlock_irqrestore(&hw->lock, flags);
837 + ltq_spi_complete(hw);
839 + return IRQ_HANDLED;
842 +irqreturn_t ltq_spi_rx_irq(int irq, void *data)
844 + struct ltq_spi *hw = data;
845 + unsigned long flags;
848 + spin_lock_irqsave(&hw->lock, flags);
850 + if (hw->rx_cnt < hw->len) {
851 + ltq_spi_rxfifo_read(hw);
853 + if (hw->tx && hw->tx_cnt < hw->len)
854 + ltq_spi_txfifo_write(hw);
857 + if (hw->rx_cnt == hw->len)
860 + ltq_spi_rxreq_set(hw);
862 + spin_unlock_irqrestore(&hw->lock, flags);
865 + ltq_spi_complete(hw);
867 + return IRQ_HANDLED;
870 +irqreturn_t ltq_spi_err_irq(int irq, void *data)
872 + struct ltq_spi *hw = data;
873 + unsigned long flags;
875 + spin_lock_irqsave(&hw->lock, flags);
877 + /* Disable all interrupts */
878 + ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
880 + /* Clear all error flags */
881 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
884 + ltq_spi_reg_setbit(hw, LTQ_SPI_RXFCON_RXFLU, LTQ_SPI_RXFCON);
885 + ltq_spi_reg_setbit(hw, LTQ_SPI_TXFCON_TXFLU, LTQ_SPI_TXFCON);
888 + spin_unlock_irqrestore(&hw->lock, flags);
890 + ltq_spi_complete(hw);
892 + return IRQ_HANDLED;
895 +static int ltq_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
897 + struct ltq_spi *hw = ltq_spi_to_hw(spi);
900 + hw->tx = t->tx_buf;
901 + hw->rx = t->rx_buf;
906 + INIT_COMPLETION(hw->done);
908 + ltq_spi_xmit_set(hw, t);
910 + /* Enable error interrupts */
911 + ltq_spi_reg_setbit(hw, LTQ_SPI_IRNEN_E, LTQ_SPI_IRNEN);
914 + /* Initially fill TX FIFO with as much data as possible */
915 + ltq_spi_txfifo_write(hw);
916 + irq_flags |= LTQ_SPI_IRNEN_T;
918 + /* Always enable RX interrupt in Full Duplex mode */
920 + irq_flags |= LTQ_SPI_IRNEN_R;
921 + } else if (hw->rx) {
922 + /* Start RX clock */
923 + ltq_spi_rxreq_set(hw);
925 + /* Enable RX interrupt to receive data from RX FIFOs */
926 + irq_flags |= LTQ_SPI_IRNEN_R;
929 + /* Enable TX or RX interrupts */
930 + ltq_spi_reg_setbit(hw, irq_flags, LTQ_SPI_IRNEN);
931 + wait_for_completion_interruptible(&hw->done);
933 + /* Disable all interrupts */
934 + ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
937 + * Return length of current transfer for bitbang utility code if
938 + * no errors occured during transmission.
941 + hw->status = hw->len;
946 +static const struct ltq_spi_irq_map ltq_spi_irqs[] = {
947 + { "spi_tx", ltq_spi_tx_irq },
948 + { "spi_rx", ltq_spi_rx_irq },
949 + { "spi_err", ltq_spi_err_irq },
952 +static int __init ltq_spi_probe(struct platform_device *pdev)
954 + struct spi_master *master;
955 + struct resource *r;
956 + struct ltq_spi *hw;
957 + struct ltq_spi_platform_data *pdata = pdev->dev.platform_data;
961 + master = spi_alloc_master(&pdev->dev, sizeof(struct ltq_spi));
963 + dev_err(&pdev->dev, "spi_alloc_master\n");
968 + hw = spi_master_get_devdata(master);
970 + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
972 + dev_err(&pdev->dev, "platform_get_resource\n");
977 + r = devm_request_mem_region(&pdev->dev, r->start, resource_size(r),
980 + dev_err(&pdev->dev, "devm_request_mem_region\n");
985 + hw->base = devm_ioremap_nocache(&pdev->dev, r->start, resource_size(r));
987 + dev_err(&pdev->dev, "devm_ioremap_nocache\n");
992 + hw->clk = clk_get(&pdev->dev, "fpi");
993 + if (IS_ERR(hw->clk)) {
994 + dev_err(&pdev->dev, "clk_get\n");
995 + ret = PTR_ERR(hw->clk);
999 + memset(hw->irq, 0, sizeof(hw->irq));
1000 + for (i = 0; i < ARRAY_SIZE(ltq_spi_irqs); i++) {
1001 + ret = platform_get_irq_byname(pdev, ltq_spi_irqs[i].name);
1003 + dev_err(&pdev->dev, "platform_get_irq_byname\n");
1008 + ret = request_irq(hw->irq[i], ltq_spi_irqs[i].handler,
1009 + 0, ltq_spi_irqs[i].name, hw);
1011 + dev_err(&pdev->dev, "request_irq\n");
1016 + hw->bitbang.master = spi_master_get(master);
1017 + hw->bitbang.chipselect = ltq_spi_chipselect;
1018 + hw->bitbang.setup_transfer = ltq_spi_setup_transfer;
1019 + hw->bitbang.txrx_bufs = ltq_spi_txrx_bufs;
1021 + master->bus_num = pdev->id;
1022 + master->num_chipselect = pdata->num_chipselect;
1023 + master->setup = ltq_spi_setup;
1024 + master->cleanup = ltq_spi_cleanup;
1026 + hw->dev = &pdev->dev;
1027 + init_completion(&hw->done);
1028 + spin_lock_init(&hw->lock);
1030 + /* Set GPIO alternate functions to SPI */
1031 + ltq_gpio_request(LTQ_SPI_GPIO_DI, 1, 0, 0, "spi-di");
1032 + ltq_gpio_request(LTQ_SPI_GPIO_DO, 1, 0, 1, "spi-do");
1033 + ltq_gpio_request(LTQ_SPI_GPIO_CLK, 1, 0, 1, "spi-clk");
1035 + ltq_spi_hw_enable(hw);
1037 + /* Read module capabilities */
1038 + id = ltq_spi_reg_read(hw, LTQ_SPI_ID);
1039 + hw->txfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
1040 + hw->rxfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
1041 + hw->dma_support = (id & LTQ_SPI_ID_CFG) ? 1 : 0;
1043 + ltq_spi_config_mode_set(hw);
1045 + /* Enable error checking, disable TX/RX, set idle value high */
1046 + data = LTQ_SPI_CON_RUEN | LTQ_SPI_CON_AEN |
1047 + LTQ_SPI_CON_TEN | LTQ_SPI_CON_REN |
1048 + LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF | LTQ_SPI_CON_IDLE;
1049 + ltq_spi_reg_write(hw, data, LTQ_SPI_CON);
1051 + /* Enable master mode and clear error flags */
1052 + ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETMS |
1053 + LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
1055 + /* Reset GPIO/CS registers */
1056 + ltq_spi_reg_write(hw, 0x0, LTQ_SPI_GPOCON);
1057 + ltq_spi_reg_write(hw, 0xFF00, LTQ_SPI_FGPO);
1059 + /* Enable and flush FIFOs */
1060 + ltq_spi_reset_fifos(hw);
1062 + ret = spi_bitbang_start(&hw->bitbang);
1064 + dev_err(&pdev->dev, "spi_bitbang_start\n");
1068 + platform_set_drvdata(pdev, hw);
1070 + pr_info("Lantiq SoC SPI controller rev %u (TXFS %u, RXFS %u, DMA %u)\n",
1071 + id & LTQ_SPI_ID_REV_MASK, hw->txfs, hw->rxfs, hw->dma_support);
1076 + ltq_spi_hw_disable(hw);
1081 + for (; i > 0; i--)
1082 + free_irq(hw->irq[i], hw);
1085 + spi_master_put(master);
1091 +static int __exit ltq_spi_remove(struct platform_device *pdev)
1093 + struct ltq_spi *hw = platform_get_drvdata(pdev);
1096 + ret = spi_bitbang_stop(&hw->bitbang);
1100 + platform_set_drvdata(pdev, NULL);
1102 + ltq_spi_config_mode_set(hw);
1103 + ltq_spi_hw_disable(hw);
1105 + for (i = 0; i < ARRAY_SIZE(hw->irq); i++)
1106 + if (0 < hw->irq[i])
1107 + free_irq(hw->irq[i], hw);
1109 + gpio_free(LTQ_SPI_GPIO_DI);
1110 + gpio_free(LTQ_SPI_GPIO_DO);
1111 + gpio_free(LTQ_SPI_GPIO_CLK);
1114 + spi_master_put(hw->bitbang.master);
1119 +static struct platform_driver ltq_spi_driver = {
1121 + .name = "ltq-spi",
1122 + .owner = THIS_MODULE,
1124 + .remove = __exit_p(ltq_spi_remove),
1127 +static int __init ltq_spi_init(void)
1129 + return platform_driver_probe(<q_spi_driver, ltq_spi_probe);
1131 +module_init(ltq_spi_init);
1133 +static void __exit ltq_spi_exit(void)
1135 + platform_driver_unregister(<q_spi_driver);
1137 +module_exit(ltq_spi_exit);
1139 +MODULE_DESCRIPTION("Lantiq SoC SPI controller driver");
1140 +MODULE_AUTHOR("Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>");
1141 +MODULE_LICENSE("GPL");
1142 +MODULE_ALIAS("platform:ltq-spi");